bluuebunny/crossref_metadata_2025 huggingface dataset:
Phase Transformation of YSZ Electrolyte in Anode-Supported SOFCs
Authors: Bai Qingchuan , Bagarinao Katherine Develos , Ishiyama Tomohiro , Yamaguchi Toshiaki , Kishimoto Haruo
Published: February 2024

Cubic-stabilized zirconia doped with 8 mol% Y2O3 (8YSZ) is a highly popular electrolyte material for solid oxide fuel cells (SOFCs) due to its exceptional oxide ionic conductivity, which remains consistent across a broad range of oxygen partial pressures. However, previous studies [1,2] have shown that the addition of nickel oxide (NiO) to 8YSZ can expedite the phase transformation process (from cubic to tetragonal) when exposed to a reducing atmosphere at relatively high temperature as 900℃. This phase transformation is closely related to the degradation of 8YSZ's conductivity. Therefore, it is crucial to investigate whether NiO, which should dissolve into the YSZ electrolyte during the co-sintering process with the NiO-YSZ anode at high temperatures, can lead to a similar phenomenon in anode-supported cells (ASCs). Hence, investigating the NiO solid solution phenomenon and its effect on the phase transformation in the YSZ electrolyte of ASCs can offer insights into its degradation behavior.

In this study, NiO-YSZ anode support and YSZ electrolyte were co-sintered at 1370℃, 1450℃, and 1550℃, respectively, for 2 hours to fabricate the half-cell samples. Subsequently, these samples were reduced at 900℃ and 700℃, respectively, with a flow of 50ccm dry H2. High-resolution secondary ion mass spectrometry (SIMS) was used to detect the presence of NiO in YSZ, and Raman spectroscopy was used to detect the phase transformation (cubic to tetragonal) occurring in the YSZ.

The SIMS results showed that the amount of NiO in the YSZ electrolyte increased with higher sintering temperatures. Moreover, after reducing the cells at 900℃, phase transformation was detected in all samples. However, there was no significant difference among those cells in terms of the degree of phase transformation, which indicated that phase transformation was not accelerated by the increase of dissolved NiO in YSZ. On the other hand, no phase transformation was observed for the cells reduced at 700℃. The mechanism of phase transformation of YSZ in anode-supported SOFCs and its related conductivity degradation will be discussed in the presentation.

References

[1] T. Shimonosono, H. Kishimoto, M.E. Brito, K. Yamaji, T. Horita, H. Yokokawa, Phase transformation related electrical conductivity degradation of NiO doped YSZ, Solid State Ionics 225 (2012) 69.

[2] H. Kishimoto, K. Yashiro, T. Shimonosono, M.E. Brito, K. Yamaji, T. Horita, H. Yokokawa, J. Mizusaki, In situ analysis on the electrical conductivity degradation of NiO doped yttria stabilized zirconia electrolyte by micro-Raman spectroscopy, Electrochimica Acta 82 (2012) 263.
K
x
Mn[Mn(CN)6] as a High Capacity Positive Electrode Material for Potassium Batteries
Authors: Hoshi Yuki , Hosaka Tomooki , Tatara Ryoichi , Komaba Shinichi
Published: February 2024

Recently, Na-ion and K-ion batteries have attracted attention as next-generation secondary batteries.1 Prussian blue analogues (PBAs) are promising cathode materials for these batteries. In 2014, it was reported that Na
x
Mn[Mn(CN)6] exhibited higher capacity in Na cells than the theoretical capacity based on Mn2+/3+ redox, which could be attributed to the reduction of Mn in [Mn(CN)6] to monovalence.2 Thus, PBA with Mn at the C-coordination site exhibits unique properties, but there is no report of high capacity in K cells. In this study, K
x
Mn[Mn(CN)6] (KMnHCM) was synthesized, and K+ ion extraction/insertion properties were evaluated.

KMnHCM was synthesized by the solution precipitation method.3 The solution was sufficiently deoxygenated by bubbling nitrogen gas, and synthesis was performed under N2 atmosphere. The obtained samples were washed three times with deionized water under N2 atmosphere, and then dried at 150 °C under vacuum. The active material was mixed with conductive carbon (KB) and binder (PVdF) at a weight ratio of 7:2:1 in a glove box under an Ar atmosphere. Galvanostatic charge-discharge tests were conducted in a two-compartment three-electrode cell using a composite electrode coated on an Al foil as the working electrode, an activated carbon counter electrode, and an Ag+/Ag reference electrode.

Figure 1(a) shows the X-ray diffraction (SXRD) patterns and Rietveld refinement results of the synthesized sample. The diffraction patterns of KMnHCM can be attributed to the monoclinic structure with space group P21/n and are almost identical to that previously reported. SXRD patterns were successfully fitted with the satisfied R values, and the composition of KMnHCM was estimated to be K1.87Mn[Mn(CN)6]0.96·0.29H2O.

Figure 1(b) shows the charge-discharge curves of KMnHCM. The electrode showed an initial charge capacity of 163 mAh g-1 and an initial discharge capacity of 220 mAh g-1, corresponding to respective ~2.0 and 2.76 potassium extraction and insertion, respectively, from/into K
x
Mn[Mn(CN)6]. The discharge capacity exceeds the theoretical capacity of 160 mAh g-1 based on the Mn2+/3+ redox of K1.87Mn[Mn(CN)6]0.96·0.29H2O. Furthermore, the additional plateau was observed at the low voltage of around 1.5 and 1.7 V in the discharge and charge curves, respectively. The extremely high capacity and the third plateau at low voltage are similar to Na
x
Mn[Mn(CN)6] in Na cells.2 Thus, the third plateau would be attributed to the reversible redox of [MnII(CN)6]4-⇄[MnI(CN)6]5-. In the talk, we will further discuss the charge-discharge mechanisms, including redox behavior and structural changes of KMnHCM during charge/discharge.

References

[1] T. Hosaka, S. Komaba, et al.,
Chem. Rev., 120 6358 (2020).

[2] Y. Cui et al., Nat. Commun.,
5, 5280 (2014).

[3] V. Renman, M. Valvo, et al.,
J. Phys. Chem. C, 123, 22041 (2019)

Figure 1
(Invited) Ion-Exchange Route for the Cathode Development of Na-Ion Batteries
Authors: Kim Haegyum
Published: February 2024

Ion-exchange reactions are frequently used to develop novel metastable electrode materials for alkali-ion batteries that cannot be synthesized (or difficult to synthesize) using direct chemical reactions. We have recently demonstrated that potassium (K)-containing compounds can be good Na+-hosting cathode materials that exhibit good electrochemical performance.[1-2] In this presentation, we will discuss, with layered oxide and polyanionic compounds as model systems, how K+-to-Na+ ion exchange occurs and how the K-containing structure benefits the electrochemical Na+ intercalation and deintercalation properties.

References

[1] H. Kim et al. Energy Storage Materials.
2022, 47, 105

[2] H. Kim et al. Advanced Functional Materials
2019, 29, 1902392
Mn-Rich P′2-Na0.67[Ni0.1Fe0.1Mn0.8]O2 As High-Energy-Densityand Long-Life Cathode Material for Sodium-Ion Batteries
Authors: Myung Seung-Taek , Choi Ji Ung
Published: February 2024

P′2-type Na0.67[Ni0.1Fe0.1Mn0.8]O2 is introduced as a promising new cathode material for sodium-ion batteries (SIBs) that exhibits remarkable structural stability during repetitive Na+ de/intercalation. The O-Ni-O-Mn-O-Fe-O bond in the octahedra of transition-metal layers is used to suppress the elongation of the Mn-O bond and to improve the electrochemical activity, leading to the highly reversible Na storage mechanism. A high discharge capacity of ≈220 mAh g−1 (≈605 Wh kg−1) is delivered at 0.05 C (13 mAg−1) with a high reversible capacity of ≈140 mAh g−1 at 3 C and excellent capacity retention of 80% over 200 cycles. This performance is associated with the reversible P′2–OP4 phase transition and small volume change upon charge and discharge (≈3%). The nature of the sodium storage mechanism in a full cell paired with a hard carbon anode reveals an unexpectedly high energy density of ≈542 Wh kg−1 at 0.2 C and good capacity retention of ≈81% for 500 cycles at 1 C (260 mAg−1).
Investigation of Sulfur Redox Chemistry in MoS2 Anodes for Potassium Ion Battery
Authors: Vijaya Kumar saroja Ajay Piriya , Han Yupei , Nason Charlie , Sankar Gopinathan , Xu Yang
Published: February 2024

Molybdenum disulfide (MoS2) with layered structure composed of molybdenum atoms coordinated with sulfur atoms makes it a suitable intercalation and conversion-based anode material for K-ion batteries (KIBs). But the electrochemical mechanism for K-ion storage in MoS2 remains unclear due to the probable occurrence of both conversion and polysulfide reactions. The formation of elemental sulfur (S0) due to irreversible conversion reaction of MoS2 is predicted to be a contributor for polysulfide reactions. Hence, in this study we utilised commercially available MoS2 as an anode for KIBs and studied the electrochemical performance by controlling the depth of discharge in the first cycle. It is identified that K-ion storage mechanism in MoS2 differs widely by operating at different discharge voltages. As a result, the characteristic voltage profile differs from the subsequent cycle, signifying dissimilar reaction pathways. Our results suggest that by controlling the depth of potassiation in MoS2, sulfur redox reactions co-exist along with conversion reaction. The existence of Mo metal and sulfur in the charge state is confirmed from various ex-situ spectroscopy studies. Moreover, formation of potassium polysulfides in the discharge state also strongly confirms the occurrence of sulfur redox reactions. Due to the dual reaction pathways, K-ion storage capacity is boosted up to 256 mAh g-1 and 93 mAh g-1 at 0.03 and 2 A g-1, respectively. The dual reaction also stabilizes the structure, which helps to attain a capacity retention of 84 % and 58 % after 500 and 1000 cycles, respectively. This study provides a mechanistic insight into the reaction pathway of K-ion storage in MoS2 when operating at various potential windows. Also, it may provide reference to utilising metal sulfides as a catalytic cathode in metal-sulfur batteries.
Long-Lasting, Reinforced Electrical Networking in High-Loading Li2S Cathode for High-Performance Lithium–Sulfur Batteries
Authors: Kim Hun , Kim Jae-Min , Sun Yang-Kook
Published: February 2024

Realizing a Li2S cathode having both high energy density and long lifespan requires an innovative cathode design that maximizes electrochemical performance and resists electrode deterioration. Herein, a high-loading Li2S-based cathode that micrometric Li2S particles are composited with two-dimensional graphene (Gr) and one-dimensional carbon nanotubes (CNTs) in the compacted geometry is developed and the role of CNTs for stable cycling of high-capacity Li-S batteries is emphasized. In a dimensionally combined carbon matrix, CNTs embedded within the Gr sheets create robust and sustainable electron diffusion pathways while suppressing the passivation of the active carbon surface. As for a unique point, during the first charging process, the proposed cathode is fully activated through the direct conversion of Li2S to S8 without the extent of incurring lithium polysulfide formation. The direct conversion of Li2S to S8 in the composite cathode is ubiquitously investigated using the combined study of in situ Raman spectroscopy, in situ optical microscopy, and cryogenic transmission electron microscopy. The composite cathode demonstrates unprecedented electrochemical properties even with high Li2S loading of 10 mg cm–2; particularly, the practical and safe Li-S full cell coupled with graphite anode shows ultra-long-term cycling stability over 800 cycles.
Catalyst Degradation Mechanism Study of Lithium-Sulfur Batteries Based on Electrodeposition
Authors: Pan Hui , Fransaer Jan
Published: February 2024

Lithium-sulfur batteries have emerged as a promising option for next-generation energy storage devices due to their high energy density and low cost. However, the two main obstacles for practical Li-S batteries are the notorious lithium polysulfide intermediate shuttle and the sluggish kinetics of sulfur cathodes, especially under lean electrolyte conditions. In this work, we propose a detailed plan to gain insight into the catalyst degradation mechanism based on electrodeposition by controlling the nucleation and deposition orientation of lithium sulfide. Firstly, we will explain why catalysts can be easily prepared by electrodeposition as cathode hosts, and others do not. Next, the key factors affecting catalysts' deactivation and cell degradation will be disclosed. Then, different types of metal catalysts with suitable particle sizes will be developed that are highly active and selective for Li-S cells. Ultimately, extensive data analysis will be performed to visualize the data and discover generalized rules for structure-activity correlation.
Ni and Fe Doped (La,Sr)TiO3 Fuel Electrodes for Solid Oxide Cells – Electrical and Electrochemical Properties
Authors: Wang Shu , Hendriksen Peter Vang , Sudireddy Bhaskar Reddy
Published: February 2024

Development of robust and impurity tolerant solid oxide cells (SOCs) has attracted a significant R&D-effort in recent years. The shortcomings of Ni-YSZ fuel electrodes in terms of redox stability, carbon and sulfur tolerance and long-term durability under strong polarization has spurred the search for alternative fuel electrode materials. Among them, doped strontium titanate materials has shown promising performance due to their good electrical transport properties, chemical and redox stability and tolerance towards impurities.

In the present study, the electrical properties of the La0.477Sr0.33Ni0.03Fe0.03Ti0.94O3-
δ (LSFNT) material, which is designed with the potential for exsoluting Ni and Fe nanoparticles, is investigated in detail. In addition, the performance of LSFNT based fuel electrodes is characterized in a symmetrical cell configuration. The electrical conductivity measurements are performed on both dense and porous LSFNT layers, as a function of temperature and pO2. The pre-reduced (1100oC, 24 hours, dry 5%H2/N2) dense LSFNT sample showed an electrical conductivity of ca. 10 S/cm at 850 oC in dry 5%H2/N2. The “in-situ reduced” (850oC, 700 hours) porous LSFNT layer showed a conductivity 10 times smaller. The conductivity was tracked as a function of pO2 showing an approximate pO2
-1/6 dependence. Also the ionic conductivity of the material was determined using an electron blocking method. At 850oC at a pO2 of 10-20 bar the ionic conductivity is ca. 0.05 S/cm at which is similar to that of Y2O3 doped ZrO2 electrolytes demonstrating that LSFNT is indeed a very good mixed ion- and electron-conducting material.

Motivated by the observed conductivities SOC fuel electrodes of LSFNT were prepared by incorporating Gd-doped CeO2 electrocatalyst into LSFNT porous backbones and their electrochemical performance was measured in 50% H2 / 50% H2O at OCV. An electrode polarization resistance of 0.05 Ω cm2 at 850oC and 0.26 Ω cm2 at 650 oC is measured for these electrodes. The polarization resistance at 850 oC is comparable to that of Ni-YSZ fuel electrodes; while at 650oC it is significantly lower in similar atmospheres. This promising electrochemical performance shows the potential of the LSFNT fuel electrodes, as an alternative to Ni-YSZ fuel electrodes, in solid oxide cell applications.
Intolerance of Ruddlesden-Popper La2NiO4±δ Structure to a-Site Cation Deficiency
Authors: Bamburov Aleksandr , Naumovich Yevgeniy , Khalyavin Dmitry , Yaremchenko Aleksey
Published: February 2024

Mixed ionic-electronic conductors derived from Ruddlesden-Popper Ln2NiO4+δ (Ln = La, Pr, Nd) attract significant attention as oxygen electrode materials for solid oxide fuel and electrolysis cells. However, literature data on the impact of A-site deficiency on the phase relationships and functional properties of Ln2NiO4+δ-based phases are contradictory. While some works report an accommodation of A-site vacancies up to x = 0.15 in La2-x
NiO4±δ, others indicate difficulties in the synthesis of single-phase La2-x
NiO4+δ even for low x values. The present work explores the impact of the nominal A-site deficiency on the phase composition and electrical transport properties of La2-x
NiO4±δ ceramics.

Ceramics with the nominal composition La2-x
NiO4±δ (x = 0, 0.02, 0.05, 0.10) were synthesized by the glycine-nitrate technique and sintered at 1350-1450°C. While XRD analysis suggested the formation of single-phase materials with orthorhombic K2NiF4-type structure, the lattice parameters remained independent of composition within the experimental uncertainty. Neutron diffraction studies of x = 0 and 0.05 samples revealed that the lattice parameters, La:Ni atomic ratio (2:1) and oxygen sites occupancy remain identical for both samples, while the presence of impurity NiO phase (0.4 wt.%) was detected for La1.95NiO4±δ. SEM/EDS inspection of ceramic samples confirmed the presence of nickel-rich inclusions for x ≥ 0.02, which could not be eliminated by increasing the temperature and time of sintering. The volume fraction of inclusions increased with x. The experimental observations are supported by the atomistic simulations showing that the coexistence of cation-stoichiometric La2NiO4+δ with nickel-rich La4Ni3O10 or NiO is more favorable compared to cation-deficient La1.95NiO4±δ. Molecular dynamics simulations of La1.95NiO4±δ lattice demonstrated that the introduction of La vacancies leads formation of instability zone in the rock-salt-type layer and destabilization of the crystal lattice. The intolerance of La2NiO4+δ lattice to A-site vacancies and coexistence of La2NiO4+δ with traces of Ni-rich secondary phase in the samples with the nominal composition La2-x
NiO4±δ results in an insignificant variation of electrical transport properties with x.

Acknowledgements

This work was developed within the scope of the project CARBOSTEAM (POCI-01-0145-FEDER-032295) funded by FEDER through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) and by national funds through FCT/MCTES, and the project CICECO-Aveiro Institute of Materials (UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020) financed by national funds through the FCT/MCTES (PIDDAC). A.B. acknowledges the PhD scholarship by the FCT (grant SFRH/BD/150704/2020). This work was partially supported by the National Science Centre, Poland, grant UMO-2020/37/B/ST8/02097.
(High-Temperature Energy, Materials, & Processes Division J. B. Wagner, Jr. Young Investigator Award) Protonic Ceramic Electrochemical Cells for Power Generation, Hydrogen Production, and Chemicals Synthesis
Authors: Duan Chuancheng
Published: February 2024

Protonic ceramic electrochemical cells (PCECs) show great promise for power generation, renewable hydrogen production, and sustainable chemical synthesis. Our laboratory at Kansas State University has made significant progress in designing PCEC materials, fabricating PCEC devices, and characterizing PCECs for various applications. In this presentation, I will first introduce our novel PCEC materials and fabrication processes, which have enabled reduced operating temperatures, enhanced performance, and improved durability. Then, I will discuss the research and development of three primary applications of PCECs by our group: power generation in fuel cell mode, green hydrogen production in electrolysis mode, and the synthesis of high-value chemicals using abundant feedstocks.
(Invited) Ruddlesden-Popper Oxides As Bi-Functional Oxygen Electrodes
Authors: Gopalan Srikanth
Published: February 2024

Incorporating more renewables into our energy mix is a major challenge that confronts our transition to a carbon free economy. Solid oxide electrochemical cells when operated alternately in fuel cell and electrolysis modes, enable the incorporation and integration of far greater amounts of solar and wind energy into our power grid. As islanded systems, they can also function as distributed generation systems thereby decreasing our reliance on the power grid. In this talk, we present a recent survey of results on rSOCs based on rare earth nickelate – rare-earth doped ceria composite oxygen electrodes that exhibit excellent cycling behavior when operated alternately in solid oxide fuel cell (SOFC) and solid oxide electrochemical cell (SOEC) modes of operation. The degradation in such cells is significantly mitigated by mode-switching operation when compared to operating in single mode operation in electrolysis mode. By comparing distributed relaxation times (DRT) analysis of impedance spectra obtained from single-mode (electrolysis) operated cells, and cells operated in switched-modes, we obtain clues into cell degradation mechanisms.
Degradation Issues in Solid Oxide Electrolysers
Authors: Laguna-Bercero Miguel A
Published: February 2024

One of the crucial aspects to achieving long lifetime and high-efficient SOCs (Solid oxide cells) is to enhance durability of the current devices.

Degradation issues are typically associated with problems in both electrodes. For example, nickel-yttria stabilized zirconia (Ni-YSZ) hydrogen electrodes present under extreme conditions of high steam partial pressures, a low durability due to Ni oxidation resulting in lowered electronic conductivity and catalytic activity of the electrode. Ni agglomeration, depleting and micro crack in Ni-containing hydrogen electrode can also occur leading to a lower activity of the Ni-based electrodes as an SOEC fuel electrode. Furthermore, carbon deposition and sulfur poisoning on the Ni surface are also lead to cell performance degradation and poor durability.

In addition, the performance of the oxygen electrode is also particularly more important in electrolysis mode than in fuel cell mode, as it is well established that electrochemically induced oxygen pressure increase at the electrolyte-oxygen electrode interface and subsequent membrane failure have been theoretically predicted and experimentally observed in SOEC mode. For example, several examples in the literature reported the presence on voids at the YSZ electrolyte, leading to delamination of the oxygen electrode. In this sense, lanthanide nickelates (Ln = La, Nd, Pr) have received considerable interest as materials for IT-SOFC electrodes and oxygen separation membranes, and they seem to be very attractive for electrolysis applications. The hyperstoichiometry of some oxygen electrode materials such as these Ruddlesden-Popper phases is believed to be favourable for effective oxygen evolution, as performance of these electrodes is enhanced in SOEC mode.

Different strategies to develop optimized electrode structures as well as controlled operating conditions will be discussed in order to improve the durability of SOCs.
Conductivity Increase As a Result of the Disappearance of Short-Range Ordering in a Scandia-Zirconia Electrolyte
Authors: Zhang Shuoshuo , Savaniu Cristian Daniel , Irvine John Thomas Sirr
Published: February 2024

Solid oxide cell electrolytes and structures have been greatly optimised to offer high performance and good durability for commercial implementation. This has highlighted an underlying issue where the slow, long-term conductivity degradation in the generally used fluorite structured oxide-ion conducting doped zirconias known to be related to reorganisation of their defect short-range structures. Among the doped zirconia systems, scandia stabilised zirconia (SSZ) gives the highest ionic conductivity due to the smallest mismatch between the dopant and host cations. However, owing to these similar and small sizes, the system is more prone to defect short-range ordering. This leads to a complex phase diagram of the Sc2O3-ZrO2 system and, depending on the composition, its ionic conductivity ages more significantly than other zirconia systems on high temperature annealing. Here, we report a magnesia and india co-doped scandia stabilised zirconia (IMSSZ) composition that offers high ionic conductivity, 0.14 at 850 ℃ and 0.4 at 1000 ℃, improved phase stability in both macro- and micro scales, and long-term conductivity stability. The conductivity after annealing the sample at 850 ℃, for different times, 0 (as-sintered), 167 and 426 hours, is correlated to the microdomain structural evolution. We show the initial of conductivity increase over time as a result of eliminating the defect short-range ordering using electron diffraction and powder neutron diffraction, resulting in a long-term stable disordered structure with improved conductivity. We will discuss here the thermodynamic driving forces for the breakdown of defect short-range ordering, and how right co-dopant sizes may play a role.

Figure 1
Effects of Doping on Conduction/Densification of BaCe0.5fZr0.3Y0.2O3-Δ Electrolyte for Green Hydrogen Applications
Authors: Fung Kuan-Zong , Tsai Shu-Yi , Tsai Yuan Jie
Published: February 2024

For reaching the goal of 2050 net-zero carbon emission, the production of green H2 needs a very efficient and cost-effective approach. A proton-solid oxide electrolyzer cell (P-SOEC) based on BaCe0.5Zr0.3Y0.2O3-δ (BCZY) proton conducting electrolyte may show some advantages such as (1) Use of lower cost metals, alloys and coatings, (3) Ease of gas sealing, (4) Reduced cost of hydrogen production. BaCe0.5Zr0.3Y0.2O3-δ (BCZY) is known for its unique stability and high proton conduction properties due to the doping effect from the substitution of Zr and Y for Ce ions. For better performance of P-SOEC, a solid electrolyte with good densification to prevent the direct mixing of fuel and oxidant is essential.

Thus, the objective of this study is to develop a cost-effective process with proper dopant in order to obtain well-densified BCZY at a temperature as low as 1200°C. For undoped BCZY, much less densification was observed. With the addition of proper dopant, BCZY may reach 97% relative density at the same temperature. It is believed that the presence of liquid phase is the reason for densification enhancement of doped BCZY. The affected electrical and structural properties will be analyzed and discussed based on sintering theory and kinetics. The crystal structure and microstructure of sintered BCZY was also characterized using XRD, field-emission SEM, and STEM.
(Invited) Zn Batteries: Stable Anode and High Energy Cathodes
Authors: Zhi Chunyi
Published: February 2024

Our research focuses on a stable aqueous Zn-based battery with long cycling stability, decent energy density, and ultimate safety performance for large-scale energy storage. To achieve this purpose, we did systematic studies on the Zn metal anode, electrolytes, and new cathode development.

For the anode side, we developed a few strategies, including pH value manipulation, ion redistribution coating, gradient coating, etc to induce stable stripping and plating of Zn. Moreover, we also found that a Zn initially plated can be much more stable than the one initially stripped during the subsequent deposition. We further utilize this observation to develop a pre-deposited Zn for Zn batteries with improved stability.

For the electrolyte, we develop a reverse micelle electrolyte, with it, the Zn anode exhibits balanced merits including strong H2 coevolution suppression, prevention of dendritic and dead Zn, inhibition of corrosion, as well as relatively fast reaction kinetics. In a more extensive context, the new reverse micelle structure of electrolytes is expected to benefit other emerging battery chemistries, where a balance between fast ion transport and sufficient stabilization against side reactions is required.

For the cathode with high energy density, we studied the critical research concerns and further potential developments of chalcogen/halogen-based batteries, primarily focusing on the electrochemically active chalcogen/halogen sources, reaction modes, soluble products, and electrolyte adaptability.

For the cathode, we use iodine as the fixing agents working in highly concentrated electrolytes to successfully enable reversible Cl-based redox electrode. The interhalogen coordinating chemistry fixes Cl in a configuration of ICl3
-. Furthermore, we simultaneously exploit two redox centers of Cl and I to realize a novel three-electrons transfer electrode, in which the Cl-I electrode can deliver remarkably high capacity up to 612.5 mAh gI
-1 and energy density as 905 Wh kgI
-1. The as-obtained energy density is 387% higher compared to the traditional one-electrons transfer of ZnǁI2 battery system and superior cycling stability with capacity retention as 95.7% after 2,000 cycles.
A Novel Aqueous Zinc-Ion Batteries with a Magnetron Sputtered SnxNy Layer with Suppressed Dendrite Formation
Authors: Kurmangaliyeva Dana , Konarov Aishuak , Bakenov Zhumabay
Published: February 2024

Thе аquеоus zіnc-іоn bаttеry іs а prоmіsіng оptіоn fоr lаrgе-scаlе еnеrgy stоrаgе systеms duе tо іts sаfеty, cоst-еffеctіvеnеss аnd еlеctrоchеmіcаl prоpеrtіеs. Hоwеvеr, thе grоwth оf dеndrіtеs оn mеtаllіc zіnc аnоdеs prеvеnts іts wіdеsprеаd prаctіcаl аpplіcаtіоn, аnd thеrе іs stіll uncеrtаіnty аbоut thе undеrlyіng mеchаnіsm оf dеndrіtе еvоlutіоn. Tо prеvеnt thіs grоwth, а prоtеctіvе lаyеr cаn bе аddеd tо thе аnоdе іntеrfаcе [1].

Thе cоmmоn prоtеctіvе lаyеrs usеd іn аquеоus zіnc-іоn bаttеrіеs (АZІBs) аrе bоrоn nіtrіdе BN [2], zinc оxіdе ZnО [3] аnd zіnc-аlumіnum аllоy Zn0.73Аl0.27 [4]. Thіs wоrk prеsеnts а Zn аnоdе dеcоrаtеd wіth а nоvеl SnxNy lаyеr thаt wаs fаbrіcаtеd by mаgnеtrоn sputtеrіng mеthоd fоr pаssіvаtіоn оf zіnc dеndrіtеs fоrmаtіоn.

А cоnductіvе tіn nіtrіdе prоtеctіvе lаyеr hаs bееn crеаtеd usіng а sіmplе аnd scаlаblе mаgnеtrоn sputtеrіng mеthоd. Thіs lаyеr hаs а hіgh zіnc аffіnіty аnd dіffusіоn bаrrіеr fоr zіnc mіgrаtіоn, lеаdіng tо mоrе еvеn zіnc dеpоsіtіоn аnd іmprоvеd еlеctrоchеmіcаl stаbіlіty. Thіs study оffеrs а nеw pеrspеctіvе fоr futurе rеsеаrch оn dеndrіtе-frее zіnc mеtаl аnоdеs thrоugh іntеrfаcіаl mоdіfіcаtіоn.

Cоmpаrеd tо bаrе Zn, zіnc thаt hаs bееn sputtеrеd wіth SnxNy prоvіdеs strоngеr Zn nuclеаtіоn sіtеs аnd lоwеr Zn оvеrpоtеntіаl, rеsultіng іn іmprоvеd Zn plаtіng/strіppіng wіth hіgh cоulоmbіc еffіcіеncy аnd lоwеr pоtеntіаl fоr hydrоgеn еvоlutіоn rеаctіоn. Thе usе оf SnxNy іn bоth symmеtrіcаl аnd zіnc-lіthіum hаlf cеlls lеаds tо lоngеr cyclе lіfе, іn cоntrаst tо uncоаtеd Zn. Thіs tеchnіquе іs а dіrеct, crеаtіvе, аnd еffеctіvе mеаns оf prеvеntіng Zn dеndrіtеs аnd оptіmіzіng thе pеrfоrmаncе оf АZІBs. Thе dеtаіls оf thе study wіll bе prеsеntеd durіng thе mееtіng.

1. Shenglin Xiong et al. Recent Progress, Mechanisms, and Perspectives for Crystal and Interface Chemistry Applying to the Zn Metal Anodes in Aqueous Zinc-Ion Batteries // Advanced Energy Materials. - 2022.- Vol. 2. -P. 114-141.

2. Xiangwu Znang et al. Nano-scale BN interface for ultra-stable and wide temperature range tolerable Zn anode // Functional Materials for Green Energy and Environment. - 2022. - Vol. 4. - P. 12190.

3. M. Masłyka et. al. Influence of absolute argon and oxygen flow values at a constant ratio on the growth of Zn/ZnO nanostructures obtained by DC reactive magnetron sputtering// Applied Surface Science. - 2016.- Vol. 389. - P. 287-293.

4. Hanfeng Liang et. al. Electrostatic Shielding Regulation of Magnetron Sputtered Al-Based Alloy Protective Coatings Enables Highly Reversible Zinc Anodes // Nano Letters.- 2022.-Vol. 3. - P. 1017-1023.

Acknowledgement

This research was supported by the research grant IRN51763/ ПЦФ- МЦРОАП РК -19 from the Ministry of Digital Development, Innovations and Aerospace Industry of the Republic of Kazakhstan “New materials and devices for defense and aerospace applications”.
Mitigating Chemo-Mechanical Degradation in Sulfide-Based All-Solid-State Batteries Comprising Sulfur Composite Cathode and Li–Si Alloy Anode
Authors: Lim Hyung-Tae
Published: February 2024

In this study, all-solid-state batteries consisting of an Li2S5–P2S5 (LPS) glass electrolyte, a sulfur/LPS glass/carbon composite cathode, and an Li–Si anode are prepared and tested under high cut-off voltage conditions (0.5–3.7 V) to elucidate the effect of LPS redox activity on the chemo-mechanical stability of LPS-based cells. The cell cycled in the voltage range 0.5–3.7 V exhibits unstable charging behaviors and voltage noise, with substantial LPS oxidative decomposition. X-ray photoelectron spectroscopy and impedance spectra analyses of a three-electrode system reveal that the cathode resistance is remarkably increased by the oxidative decomposition of LPS when the cell is charged to 3.7 V, which induces dendritic lithium growth at the anode side, resulting in a micro-short circuit through the electrolyte. Composite anodes of Li3PS4 glass+Li–Si alloy (Type 1) and Li3N+LiF+Li–Si alloy (Type 2) are also prepared for all-solid-state batteries (ASSBs) with LPS glass electrolyte and sulfur/LPS glass/carbon composite cathode. Using a three-electrode system, the anode and cathode potentials are separated, and their polarization resistances are individually traced. Even under high-cutoff-voltage conditions (3.7 V), Type 1 and 2 cells are stably cycled without voltage noise for >200 cycles. Although cathode polarization resistance drastically increases after 3.7 V charge owing to LPS oxidation, LPS redox behavior is fairly reversible upon discharge–charge unlike the non-composite alloy anode cell. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) analysis reveals that the enhanced cyclability is attributed to uniform Li–Si alloying throughout the composite anode, providing more pathways for lithium ions even when these ions are over-supplied via LPS oxidation. These results imply that LPS-based cells can be reversibly cycled with LPS redox even under high-cutoff voltages, as long as non-uniform alloying (lithium dendrite growth) is prevented.
(Invited) Controlling Metal Exsolution on Oxides By External Drivers – Role of Elastic Strain and Ion Irradiation
Authors: Yildiz Bilge , Wang Jiayue
Published: February 2024

Exsolution is an effective approach to fabricating oxide-supported metal nanoparticle catalysts via phase precipitation out of a host oxide. A fundamental understanding and control of the exsolution kinetics are needed to engineer exsolved nanoparticles to obtain higher catalytic activity toward clean energy and fuel conversion. Since oxygen release via oxygen vacancy formation in the host oxide is behind oxide reduction and metal exsolution, we hypothesize that the kinetics of metal exsolution should depend on the kinetics of oxygen release. In this work, we probe the surface exsolution kinetics both experimentally and theoretically using thin-film perovskite oxide model systems, show its relation to the oxygen evolution kinetics. We also tune defect formation and the resulting metal exsolution, by external drivers including elastic strain and ion irradiation. Using both of these external drivers, we couple to the formation of point defects and defect clusters, that serve as nucleation sites for nanoparticle exsolution. As a result, we can controllably tune size, density, composition and position of the exsolved metal nanoparticles.
(Invited) Ultrafast Electrodeposition of Faceted Li Metal
Authors: Li Yuzhang
Published: February 2024

Electrochemical deposition of metals with precise morphological and chemical control is of fundamental importance to a broad range of electrochemical systems, including energy storage, large scale manufacturing, electronics, and electrocatalysis. For non-reactive metals (e.g. Ni, Pt), electroplating is a commercially established process that gives the desired control of deposition morphology and chemistry. However, deposition of reactive metals (e.g. Li, Na) critical for enabling next-generation batteries is complicated by metal surface corrosion that occurs concurrently with metal deposition, making such electrodeposition processes neither well-understood nor well-controlled. This work highlights the electrodeposition of lithium (Li), a reactive metal anode plagued with uncontrolled dendritic morphologies and surface corrosion, both of which are intimately linked and occur simultaneously. Despite tremendous research efforts to mitigate these issues, common literature descriptions of Li metal deposits (e.g. “chunky”, “pancake”) and their corrosion films (e.g. “strong”, “stable”) are ill-defined and often qualitative, highlighting our incomplete understanding of the deposition process and hindering the practical application of high energy battery chemistries enabled by Li metal. Our work seeks to bridge this critical gap in understanding by solving the fundamental challenge of (1) decoupling simultaneous electrodeposition from surface corrosion of reactive metals and (2) observing their reactive nanoscale interface.
LIOVIX® Printable Lithium Technology for Lithium Anode Manufacturing at Scale
Authors: Xia Jian , Fitch Brian , Yakovleva Marina
Published: February 2024

The commercialization of lithium metal batteries requires the mass production of cost-effective thin lithium metal foil with thickness less than 30 µm. However, today’s known technologies are not yet commercially available. For example, thin lithium metal foil can be produced by hydraulic extrusion followed by a rolling process. This process usually requires a delicate balance between the pressure and tension created by both extruder and winder, so that the resulting foil is not torn or stretched, retaining all the dimensional characteristics required. This process can be extremely challenging when making lithium metal films with thickness less 20 µm due to the poor mechanical properties of lithium metal. Lithium metal foil can also be produced by physical vapor deposition (PVD). Lithium metal foil produced by PVD process are generally homogenous and have good control in thickness. However, PVD technology requires high vacuum chamber and is slow in the deposition rate, typically in the range of 0.1 to 100 nm s−1, making industrial scale of 20 µm lithium foil very challenging1.

Livent has developed LIOVIX®printable lithium technology, a proprietary formulation that combines Stabilized Lithium Metal Powder (SLMP®), rheology modifiers and solvent to produce a stable suspension that can be printed on most common substrates. LIOVIX®printable lithium technology is an enabling technology that can produce thin lithium foil with thickness of 5 µm to 50 µm with no limitation in width, length and at high deposition speed. LIOVIX®enables pattern printing and can be applied to any substrate, for example a prefabricated anode, cathode, current collector, separator, and solid or polymer electrolyte. This technology enables 3D battery printing in a custom form factor shape.

In this presentation, we will cover thin lithium foil manufacturing processes using standard industrial equipment and electrochemical performance results.

References

Acebedo, Begoña, et al. "Current Status and Future Perspective on Lithium Metal Anode Production Methods." Advanced Energy Materials (2023): 2203744.
FeF2-Li Batteries in Ionic Liquid Electrolytes
Authors: Olbrich Lorenz Frank , Sanghadasa Mohan , Pasta Mauro
Published: February 2024

The electrification of the aviation industry requires secondary batteries that meet strict technical specifications, which cannot be achieved by current lithium-ion cells. A step improvement in stack-level energy densities in addition to safer battery chemistries compatible with operations at temperatures up to 80°C are necessary to minimize water-cooling requirements and their adverse impact on energy density. [1]

Lithiation of transition metal fluorides (TMFs) cathodes occurs via a two- or three-electron transfer conversion mechanism, enabling an increase in theoretical energy density by 200% to 300% compared to conventional intercalation compounds. [2]

Ionic liquids (ILs) are characterized by their high thermal stability, little to no flammability, and low vapor pressure. [3]

Combining TMF cathodes with a lithium metal anode and an IL electrolyte results in a battery with a high energy density, safe cell operation, and high-temperature compatibility suitable for applications in electric aviation. [4, 5]

Here we present the progress we have made in the development of secondary FeF2-IL-lithium-metal batteries. Through a systematic investigation of active material particle morphology and carbon composite preparation techniques, we have been able to demonstrate stable capacity retention for over 500 cycles.

A post-mortem characterization analysis elucidates the role of the IL in forming stable interphases with both anode and cathode materials and on their ageing mechanism at room and elevated (80°C) temperatures.

Viswanathan, V. et al. The challenges and opportunities of battery-powered flight. Nature 601, 519–525 (2022).

Wang, L. et al. Li-free Cathode Materials for High Energy Density Lithium Batteries. Joule 3, 2086–2102 (2019).

Maton, C., De Vos, N. & Stevens, C. V. Ionic liquid thermal stabilities: Decomposition mechanisms and analysis tools. Chemical Society Reviews 42, 5963–5977 (2013).

Xiao, A. W. et al. Understanding the conversion mechanism and performance of monodisperse FeF2 nanocrystal cathodes. Nature Materials 19, 644–654 (2020).

Olbrich, L. F., Xiao, A. W. & Pasta, M. Conversion-type fluoride cathodes: Current state of the art. Current Opinion in Electrochemistry 30, 100779 (2021).

Figure 1
Metal(Pt, Pd)-Perovskite Oxide(Ba0.5Sr0.5Co0.8Fe0.2O3-δ) Hybrid Material As a Bifunctional Electrocatalyst for Lithium-Air Battery
Authors: Shin Seoyoon , Lee Seokhee , Shin Tae Ho
Published: February 2024

The rapid depletion of fossil fuel resources and growing concerns over climate change have made the development of next-generation batteries a top priority. Among these, Li-O2 batteries have attracted significant interest due to their potential for much higher gravimetric energy storage density compared to other chemical batteries. However, efficient and cost-effective catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are critical for the efficient functioning of these batteries.

In recent years, complex perovskite oxides, such as Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF), have been identified as promising candidates for bifunctional catalysts due to their defective structures and excellent oxygen mobility. However, while BSCF exhibits high OER activity, its ORR performance is poor. To address this issue, researchers have turned to metal-oxide composite catalysts, where nanosized metals are deposited on the surface of perovskite oxides, to increase activity and stability towards ORR due to the synergistic effect between metal and oxide support.

In this study, we report the development of bifunctional electrocatalysts with highly electrocatalytic activity for ORR and OER. We used a simple wet-chemical processing technique to deposit metal catalysts with superior ORR activity on perovskite oxide-based catalysts with high OER activity. The direct deposition method is an effective way to create a good distribution of metal catalysts, intimate contact between metal catalysts and BSCF perovskite oxide, which may contribute to the creation of a synergistic effect between them. Our results showed that the metal catalysts deposited on perovskite oxides of Pd@BSCF and Pt@BSCF exhibited better ORR activity than others and higher OER activity than the perovskite oxides alone, resulting in much-enhanced bifunctionality through a synergistic effect between the metal catalysts and perovskite oxides.

We further investigated the enhanced bifunctional electrocatalytic activity of the metal catalysts deposited perovskite oxides for Li-O2 batteries. The assembled Li-O2 batteries with Pd@BSCF cathode demonstrated lower discharge/charge overpotential (0.8 V at the cutoff capacity of 500 mAh gcat
-1) and improved cycling stability (over 70 cycles), indicating the effectiveness of our approach in enhancing the bifunctional activities of ORR and OER for application in electrochemical energy storage and conversion systems. The encouraging results obtained from this study might have been attributed to two mechanisms, namely, the synergistic effect of electronic transfer and RDS/spillover. Our study suggests that the deposition of metal catalysts on the surface of perovskite oxides (Pd@BSCF and Pt@BSCF) is an effective approach to enhance bifunctional activities of ORR and OER, making it a promising strategy for the development of next-generation batteries.

Figure 1
Zinc Slurry Electrodes for Double Flow Zinc-Nickel Batteries
Authors: Opitz Martin , Sörgel Seniz
Published: February 2024

Lithium-based systems are still the major storage technology especially in mobile applications like electromobility and consumer electronics. However, in the field of stationary energy storage devices, redox-flow batteries exhibit significant advantages because energy and power can be scaled independently and the device can be discharged up to 20 h, in contrast to lithium-ion batteries.[1] In the field of redox-flow batteries, the main focus is placed on vanadium-based systems. However, vanadium-based systems have some drawbacks due to the low gravimetric energy densities, the toxicity [2] and the high price of vanadium [3], as well as the short life span of the membrane separating the half-cells.[4]

In our research project NiZi-Flow², a new concept of flow cells based on nickel and zinc is investigated, in which slurries of zinc and nickel-hydroxide particles are pumped through the flow battery, respectively. Our part in the project is the examination of the electrodeposition and dissolution of zinc under idealized conditions to obtain the influence of flow and current density parameters on the zinc surface morphology. To study the zinc half-cell, a stirred electrochemical cell was designed and cycling experiments with the zinc slurry were performed.

M. Skyllas-Kazacos, M.H. Chakrabarti, S.A. Hajimolana, F.S. Mjalli, M. Saleem, J. Electrochem. Soc., 158 (2011) R55.

A. Ciotola, M. Fuss, S. Colombo, W.-R. Poganietz, J. Energy Storage, 33 (2021) 102094.

T. Nguyen, R.F. Savinell, Electrochem. Soc. Interface, 19 (2010) 54–56.

A.Z. Weber, M.M. Mench, J.P. Meyers, P.N. Ross, J.T. Gostick, Q. Liu, J. Appl.
Electrochem., 41 (2011) 1137–1164.
Exsolution of Co Nanoparticles on La2Ti2O7 for Efficient OER/ORR Reaction
Authors: Zhang Hong , Zhang Hong
Published: February 2024

Exsolution is a promising approach for enhancing the catalytic performance of perovskite materials and has attracted significant attention in recent years. In this study, we demonstrate the preparation of La1.9Co0.1Ti1.9O7-δ through a simple exsolution method and evaluate its efficacy as an electrocatalyst for the OER/ORR reaction. Our experimental results indicate that the electrocatalytic activity of the cobalt-decorated catalyst is several times higher than that of the pristine La2Ti2O7. Moreover, the exsolved sample exhibits excellent stability during testing. In-depth characterization has revealed that the remarkable enhancement in activity is related to several factors, including a large surface area, low electrochemical impedance, and enhanced reaction kinetics. These findings suggest that nanoparticle exsolution is a highly promising strategy for the development of high-performance electrocatalysts.
Facile Fabrication of Indium-Doped TiO2 Via Anodization As Photoanodes for Photoelectrochemical Water Splitting Under Visible Light
Authors: Sharma Shuchi , Kannan Arunachala Mada , Gangavarapu Ranga Rao
Published: February 2024

Directionality of Nanostructured forms of TiO2 prepared through electrochemical anodization as photoanodes in photoelectrochemical (PEC) water splitting benefits the efficient e- and h+ separation. However, a large band gap hinders using such nanostructures in the presence of visible light. Doping with metals can be one of the strategic ways to reduce band gaps. In the present work, single-step anodization of titanium foils in the viscous electrolyte containing different concentrations of indium metal salt is used to fabricate Indium-doped TiO2 nanostructures. The anodization samples are annealed to obtain the photoactive anatase phase of TiO2. As prepared, Indium-doped TiO2 structures are characterized by field emission scanning electron microscope, X-ray diffraction, and UV-Vis light diffuse absorbance spectroscopy. PEC water splitting activity of Indium-doped TiO2 nanostructures is tested in 1 M KOH using a Xe-arc lamp equipped with an AM1.5 G filter under 1 sun. Indium doping enhances the photocurrent, photostability, and charge separation properties compared to the bared TiO2 nanostructures. This work shows that doping the optimum amount of Indium affects the PEC activity of the photoanodes through increased TiO2 lattice defects, and electrical conductivity.