bluuebunny/crossref_metadata_2025 huggingface dataset:
Modifying the Cathode Catalyst Layer in PEM Fuel Cells with Ionic Liquids for Improved Oxygen Reduction Reaction
Authors: Gawas Ramchandra , Tang Maureen , Snyder Joshua David
Published: November 2022

Increasing the accessibility of green, affordable hydrogen and reducing the cost of polymer electrolyte membrane fuel cells (PEMFC) devices are critical to the widespread commercialization of hydrogen powered fuel cells. The high cost of PEMFCs is in part due to the high Pt leadings in the cathode catalyst layer (CCL) to compensate for kinetic and transport losses during the sluggish oxygen reduction reaction. Therefore, substantial research efforts have been focused on modifying the CCL and its constituent components to achieve cost parity with other advanced energy technologies, particularly in the transportation sector.

Hydrophobic ionic liquids (ILs) have been used as interfacial additives for oxygen reduction reaction (ORR) electrocatalysts, demonstrating enhanced catalyst activity and durability.1,2 However, incorporating ILs or IL-modified catalysts into the electrodes of a PEMFC membrane electrode assembly (MEA) has proven to be challenging. To address this limitation, we developed a new ionomer chemistry with orthogonal properties of protonic conductivity and ionic liquid functionality: sulfonated poly(ionic liquid) block copolymers (S-PILBCPs). The new ionomer in the Pt/C CCLs yields a two-fold improvement in the kinetic activity, both in the half-cell and MEA. Furthermore, a Nafion/S-PILBCP composite ionomer substantially improves the high current density performance as well.3

In this work, we use rotating disk electrode (RDE) techniques to electrochemically characterize the Pt/S-PILBCP interface. Our analysis demonstrates the promise and utility of hydrocarbon-based poly(IL) ionomers over the traditional ionomer-Nafion and also provides important insights about observed MEA performance enhancements.

References:

Snyder, J., Fujita, T., Chen, M. W. & Erlebacher, J. Oxygen reduction in nanoporous metal-ionic liquid composite electrocatalysts. Nat. Mater.
9, 904–907 (2010).

Li, Y., Hart, J. L., Profitt, L., Intikhab, S., Chatterjee, S., Taheri, M. & Snyder, J. D. Sequential Capacitive Deposition of Ionic Liquids for Conformal Thin Film Coatings on Oxygen Reduction Reaction Electrocatalysts. ACS Catal.
9, 9311–9316 (2019).

Li, Y., Cleve, T. Van, Sun, R., Gawas, R., Wang, G., Tang, M., Elabd, Y. A., Snyder, J. & Neyerlin, K. C. Modifying the Electrocatalyst−Ionomer Interface via Sulfonated Poly(ionic liquid) Block Copolymers to Enable High-Performance Polymer Electrolyte Fuel Cells. ACS Energy Lett.
5, 1726–1731 (2020).
(Digital Presentation) Electrochemical Analysis of Oxygen Reduction in Phosphonium Ionic Liquids Based on Rotating Ring-Disk Electrode Method
Authors: Oi Yuri , Okada Takuya , Matsumoto Mitsuhiro , Katakura Katsumi , Inoue Yohtaro , Tsunashima Katsuhiko , Yamada Hirohisa
Published: November 2022

Ionic liquids (ILs) have characteristic physicochemical properties such as high thermal stability, low volatility, low melting point, and flame resistance. Moreover, ILs exhibit also excellent electrochemical properties represented by a wide potential window.[1] Hence, they have a great potential for electrochemical applications such as electrolytes for batteries, capacitors, fuel-cells and so on. Phosphonium ILs have unique physical characters such as lower viscosity and higher ionic conductivity compared with corresponding structured ammonium ILs.[2] Recently, we have evaluated the diffusion coefficient and the solubility of oxygen molecules in phosphonium ILs and have clarified that such oxygen behaviors strongly depends on the chemical structure of cation rather than that of anions. In the present study, we demonstrated the proton effect for the ORR in phosphonium ILs using rotating ring disk electrode (RRDE) technique.[3] Tetraalkyl-phosphonium(PXXXY+ and bis(trifluoromethane sulfone) imide (TFSA-)) ILs were used for electrolytes.

Cyclic voltammetry (CV) and convective voltammogram were performed using a three electrode cell at 25oC. The RRDE constructed a glassy carbon (GC) or platinum (Pt) disk, and Pt ring electrodes were used as the working electrodes. The ring current was measured at a potential of 1.0 V vs. Ag/Ag+ reference electrode, where the intermediate oxidation reaction enough attached to diffusion limit.

In the non-protonic media, ORR currents were observed from –0.6 V on GC disk electrode and –0.5 V on Pt disk electrode respectively, which were corresponding to the one-electron reduction reaction in ORR. On the other hand, the on-set potential of ORR in protonic media was higher than that in non-protonic media on both electrodes. Such potential shifts were strongly appeared on the Pt disk electrode than that on the GC disk electrode. Moreover, the diffusion limiting current was observed on Pt disk electrode at higher potential region in protonic media, and the current increased with increasing H-TFSA content. Therefore, the limiting current originated from not the transport of oxygen molecules, but that of proton, while the ring current oppositely decreased with increasing H-TFSA content. The ring current originated from intermediate formed on Pt disk electrode was smaller than that on GC disk electrode. These results indicated that the number of electrons in ORR increased by the existence of proton, and the effect of proton was promoted on Pt surface better than the GC surface.

[1] A. Khan, C. Zhao, ACS sustainable Chem. Eng.
4, 506 (2016)

[2] K. Tsunashima, and M. Sugiya, Electrochemistry Communications, 9, 2353- 2358(2007)

[3] M. Hildera, et al, Electrochimica Acta, 202, 100-109(2016).
Stabilization of Urea in Urine through the Electrochemical Generation of Hydrogen Peroxide
Authors: Arve Philip
Published: November 2022

Urine represents a small fraction, usually 1-2%, of the total volume of a typical wastewater stream, but contributes over half of the nitrogen. This nitrogen, which is predominantly ammonium, must be removed prior to discharging the treated wastewater into the environment. Traditional nitrogen removal processes are often energy intensive and operationally sensitive. Source separation of urine presents an opportunity to divert most of the nitrogen received by a traditional wastewater treatment plant and allow direct treatment of this highly concentrated waste stream. Source separation of urine is not without its own operational difficulties though; flushless urinals often succumb to clogging and foul odors. This is in part due to the hydrolysis of urea by the urease enzyme which converts urea, the principal nitrogen compound in urine, to ammonia. This in turn produces odors and precipitates minerals which lead to mineral scaling. Source separated urine is also susceptible to biological growth, which along with scaling, are the primary causes of plumbing fixture failures in source separation installations. Source separated urine has been identified as a potential candidate for resource recovery, but the instability of fresh urine presents operational hurdles that must be overcome. The hydrolysis of urea by urease may be inhibited by dosing fresh urine with a sufficient volume of strong acid or base, or by strong oxidants such as hydrogen peroxide. These stabilizers are hazardous materials, and bulk storage of these chemicals presents inherent danger. We have investigated the use of electrochemical cells capable of producing hydrogen peroxide in-situ
in fresh urine to determine the feasibility of this technology for urine stabilization. Urine is fed to the cathode chamber where a gas diffusion electrode reduces atmospheric oxygen to hydrogen peroxide, which deactivates any urease present in the urine. An added benefit to using hydrogen peroxide is its biocidal properties; urine samples treated with this approach displayed no biological growth after extended storage. Previous experiments have utilized exogenously added jack bean urease to simulate conditions present in source separated urine collection systems; control samples with no hydrogen peroxide present exhibited complete disappearance of urea, while samples with electrochemically synthesized hydrogen peroxide remained stable. Current experiments are exploring the long-term stability of treated urine after exposure to ureolytic bacteria to better simulate real world applications of this treatment approach.
Cross-Linked Phenyl-Acrylate-Based Anion Exchange Membranes Synthesis, Characterization and Performance in Non-Aqueous Redox Flow Battery
Authors: Mazumder MD Motiur Rahaman , Minteer Shelley D.
Published: November 2022

Abstract

The development of redox flow batteries (RFBs) has been one of the primary responses to the need to store harvested renewable energy for improving grid reliability and utilization.1–4 In this study, we synthesized and characterized seven types of Phenyl acrylate (PA) backbone-based anion-exchange membranes (AEM) and explored the performance of AEMs in non-aqueous redox flow batteries under ideal conditions. IR data (Figure 1 ) confirms the incorporation of ion carriers in the PA backbone. Methacroylcholine chloride (MACC) was used as an anion carrier, N, N-Methylenebis acrylamide (MBAA) was used as a cross-linker, and 1-Hydroxycyclohexyl phenyl ketone (HCPK) was used as a photoinitiator. Performance was compared based on high stability in a non-aqueous solvent, high permeability to the charge-carrying ion, low electric cell resistance, low cross-over of the redox-active molecules, high mechanical property, and low cost. The best membraned will be found which will show no cross-over of redox-active electrolytes after 1000 battery cycle experiments and exhibit low resistance and high structural/chemical stability in MeCN solvent.

References

(1) Mazumder, Md. M. R.; Burton, A.; Richburg, C. S.; Saha, S.; Cronin, B.; Duin, E.; Farnum, B. H. Controlling One-Electron vs Two-Electron Pathways in the Multi-Electron Redox Cycle of Nickel Diethyldithiocarbamate. Inorg. Chem.
2021, 60 (17), 13388–13399. https://doi.org/10.1021/acs.inorgchem.1c01699.

(2) Mazumder, M. M. R.; Farnum, B. H. Two One Electron vs One Two-Electron Redox System of Nickel Diethyldithiocarbamate for Redox Flow Battery; ACS, 2021. https://doi.org/10.1021/scimeetings.1c00951.

(3) Mazumder, M. M. R. Ni(IV/II) Redox Couple 2e- Reversibility Improvement for Redox Flow Battery. ECS Meet. Abstr.
2021, MA2021-02 (5), 1855–1855. https://doi.org/10.1149/ma2021-0251855mtgabs.

(4) Islam, R.; Mazumder, M. M. R.; Farnum, B. H. Solvent Dependent Spectroscopic and Electrochemical Studies of Nickel (II) Diethyldithiocarbamate for Energy Storage. ECS Meet. Abstr.
2021, MA2021-01 (1), 54–54. https://doi.org/10.1149/ma2021-01154mtgabs.

Figure 1
Morphology of Transition Metal Carbonate Cathode Precursors
Authors: Barai Pallab , Wolfman Mark , Wang Xiaoping , Chen Jiajun , Gutierrez Arturo , Garcia Juan , Wen Jianguo , Fister Tim , Iddir Hakim , Srinivasan Venkat
Published: November 2022

Increasing the capacity of cathode materials used for lithium-ion batteries is desirable, as it ultimately enhances the energy density. Due to their lower cost and reversible cycling capacity of 250 – 300 mAh/g, Li- and Mn-rich LMR-NMC oxides are strong candidates as next generation cathodes used in lithium-ion batteries. Apart from the atomic structure, morphology of the cathode particles also influence their performance. LMR-NMC cathode particles are usually constructed through a two-step cathode fabrication process, which involves initial coprecipitation of the Mn-rich carbonate based cathode precursors, and later calcination of these precursors with a lithium salt at elevated temperatures. The secondary particles generally maintain their as precipitated precursor morphologies even after high temperature calcination. Even though the primary particles do change their size during calcination, the rate of oxidation and lithiation experienced by the transition metal precursors depend substantially on the primary particle morphology. Hence, it is critical to understand and control both the primary and secondary particle morphologies obtained after the coprecipitation process. In the present context, carbonate based NMC cathode precursors containing only Mn, only Ni and only Co, is precipitated, along with equal amount of the transition metals (Ni0.33Mn0.33Co0.33CO3), using conventional batch reactors. NH4HCO3 is used as the source of carbonate anions during the coprecipitation process, and the entire reaction is conducted at 50°C. The obtained particle morphologies for different transition metals are shown in Figure 1(a) as visualized using high resolution TEM techniques. Except MnCO3, all other transition metals demonstrate aggregated morphologies, which most probably form through surface growth mechanisms. Competition between growth rate and surface energies that leads to the formation of single crystalline particles for MnCO3, and particulate features for other transition metals, are demonstrated in Figure 1(b). Multiscale computational methodologies are developed to elucidate the impact of reaction kinetics and thermodynamics on determining the overall primary and secondary particle morphologies. Influence of transition metal content and ammonia concentration in determining the final particle size and size distribution will be discussed as part of this study.

Figure 1
Electric-Field-Assisted Ultrasonic Spray Pyrolysis of Solid State Electrolytes
Authors: Liu Lin , Albert Cade , Wu Huixuan
Published: November 2022

Solid polymer electrolytes (SPEs) hold the potential to revolutionize energy storage by enabling secondary batteries containing lithium metal anodes, which have ultra-high theoretical capacity of 3860 mAh g−1, compared to a typical graphite anode’s theoretical capacity of 372 mAh g−1. The bulk of SPE research focuses on optimizing SPE chemistry, while the manufacturing process receives little attention. In this interdisciplinary study, as shown in Figure 1, an electric-field-assisted ultrasonic spray pyrolysis (EFAUSP) setup is proposed and integrated with a cyclone-separator, which was simulated ANSYS Fluent, then built based on the results. Digital in-line holography is performed to determine the droplet size distribution and investigate the droplet trajectories near the substrate surface. This newly proposed EFAUSP setup is based on a 3D printer controller, promising macrostructure and microstructure control in future work. Future work will build upon these results to investigate the mechanical and electrochemical properties of the deposited SPEs.

Figure 1
High Entropy Spinel Oxide As a Bifunctional Electrocatalyst for Rechargeable Zinc-Air Battery
Authors: Gaolatlhe Lesego , Lebechi Augustus Kelechi , Haruna Aderemi Bashiru , Mofokeng Thapelo Prince , Mwonga Patrick Vaati , Ozoemena Kenneth Ikechukwu
Published: November 2022

Rechargeable zinc-air battery (RZAB) represents one of the ‘beyond-the-lithium-ion’ battery technologies with great potential for renewable energy storage. It is safe, environmentally benign, and excellent potential for affordable applications in resource-limited countries, ranging from residential and industrial electricity supply, transport (e.g., electric vehicles) to mobile and consumer electronics markets. RZABs possess high theoretical specific energy density of 1086 Wh/kg, which is 5 times greater than that of the conventional lithium-ion battery (LIB). The key challenge that conspires against the widespread commercialization of RZAB is the sluggish oxygen reaction kinetics that impedes reversibility of the system. Thus, it has become quite critical to develop low-cost and high-performance bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) [1,2].

High entropy materials (HEMs) have emerged as electrocatalysts for ORR and OER. HEMs contain five or more metals in equal proportions. Their unique conformational entropy and physico-chemical properties (including lattice distortion, synergistic effects amongst the different metals, and rich defect chemistries) promise to improve the kinetics of ORR / OER and electrochemical cycling stability. In this work, the high entropy spinel oxide, (CoCuFeMnNi)3O4 supported on conductive carbon has been synthesized and characterised using XRD, XPS, HRTEM, SEM and others. Preliminary electrochemistry shows improved ORR/OER kinetics. This presentation will discuss the performance of the initial lab-based RZAB using this electrocatalyst.

References

AB Haruna and KI Ozoemena, Manganese-based bifunctional electrocatalysts for zinc-air batteries, Opin. Electrochem. 2020, 21, 219-224

AK Ipadeola, AB Haruna, L Gaolatlhe, AK Lebechi, J Meng, QQ Pang, K Eid, AM Abdullah, and KI Ozoemena, Efforts at Enhancing Bifunctional Electrocatalysis and Related Events for Rechargeable Zinc-Air Batteries; ChemElectroChem 2021, 8, 3998-4018
Designing a Reference Electrode – an Approach to Fabricate Laser Perforated Reference Electrodes for Lithium-Ion Batteries
Authors: Rutz Daniel , Bauer Ingolf , Brauchle Felix , Jacob Timo
Published: November 2022

The implementation of reference electrodes (RE) in lithium-ion battery cells represents a promising way to optimize fast-charging, evaluate the C-rate capability of new electrode materials, and monitor cell aging more precisely. However, their design and material choice are under debate. Recently, lithium titanate oxide (LTO, Li4Ti5O12) and lithium iron oxide (LFP, LiFePO4) have been dip-coated onto wide-meshed metal nets to reduce the blocking effect. Still, this process is elaborate and not common in electrode manufacturing.

In this study, we show a new post-processing method to fabricate user-defined REs based on LFP via an ultrashort pulse laser. The REs were designed in such a way that the blocking of the Li+ ion pathways should be as small as possible. Testing these special REs in NMC811/graphite full pouch cells revealed slim to no influence on the cell capacity while delivering reproducible voltages, even at high C-rates. Moreover, cell thickness change measurements at the RE site during cycling and post-mortem analysis showed no sign of blocking.
The Effect of Ionic Carriers and Degree of Solidification on the Solid-State Electrolyte Performance for Free-Standing Carbon Nanotube Supercapacitor
Authors: Ashraf Juveiriah M. , Ghodhbane Myriam , Busa Chiara
Published: November 2022

To eliminate electrolyte leakage, the development of safe and flexible supercapacitors necessitates solid-state electrolytes which integrate both high mechanical and electrochemical capabilities. Quasi-solid-state electrolytes, which constitute a polymer matrix along with an aqueous electrolytic phase, are a viable answer to this problem. Recently, gel electrolytes have gained a lot of attention in flexible and wearable electronic devices due to their remarkable advancements. However, the limitation in the multi-functional abilities and high-performance in such gels hinders the practical usage of such devices. On the electrochemical perspective, the performance of the gel electrolyte depends on the type of ionic carrier (acidic, alkaline, or salt-based), size of the ion, solvent concentration, type of polymer, as well as the interaction between the polymer and other components. Moreover, the performance of the electrolyte differs with the electrode-electrolyte interface and thus is highly dependent on the electrode material. For this reason, it is vital to carry a parametric study to evaluate the effect of the above stated. The aim of this study is to investigate the effect of changing the ionic carrier (namely H3PO4, KOH and LiCl) as well as the solvent concentration on architecturally engineered PVA-based electrolytes’ performance in free-standing CNT supercapacitor using a bio-based compound, cellulose as a binder. The dependence of the electrolyte’s mechanical structure for long term stability is further evaluated by using the optimized concentration of each (H3PO4, KOH and LiCl) by freezing and de-freezing the gel to form membrane-like films, as a result of the increased physical cross-linking. The supercapacitors are studied for their capacitance, charge/discharge capabilities as well their long-term stability and also compared with aqueous electrolyte for the three aforementioned ionic carriers.
Degradation Behavior of 21700 Cylindrical Lithium-Ion Cells during over-Discharge Cycling at Low Temperature
Authors: Kim Eunsae , Song Jihun , Lim Jaejin , Lee Hyobin , Kim Dohwan , Lee Yong Min
Published: November 2022

In case of electric vehicles (EVs) and energy storage systems (ESSs), multiple lithium-ion battery (LIB) cells are connected in series or parallel to supply the required capacity and power of appliances. However, there is inevitably a small difference in capacity among mass-produced cells. Furthermore, all the cells cannot degrade at the same rate in long-term usage. Thus, relatively more degraded cells in the module or pack can be over-charged or over-discharged, which can trigger the thermal runaway of LIBs. In this sense, many research groups have investigated the behaviors of over-charged cells with experiments and simulation works. However, the over-discharge was not dealt as much as the over-charge, even though the over-discharge can frequently occur and must be one of the electrical abuses. Especially, most of the over-discharging studies have been limited to room-temperature degradations like Cu dissolution, SEI decomposition, etc. However, considering the wider operating temperature of EVs and other applications, it is also necessary to investigate this over-discharging behavior at various temperatures.

Thus, in this work, we reveal how the operating temperature (-20 ℃, 25 ℃) and over-discharge cycling influence the degradation behavior of 21700 LIB cells through both electrochemical analysis (EIS and DC-IR) and postmortem analysis (SEM, EDS, XPS, and XRD). Furthermore, we constructed a thermo-electrochemical model applicable to the over-discharge condition (0 V cut-off at -20 ℃ and 25 ℃). Thus, we can systematically study the abnormal thermal behavior of over-discharged cells at the low temperature. This result will be a good case study how the over-discharge affects the LIB cells at low temperatures.
Morphological & Structural Control of Electrodeposited Sb Anodes through Solution Additives and Their Influence on Electrochemical Performance in Na-Ion Batteries
Authors: Nieto Kelly , Gallawa Jessica Ruby , Prieto Amy L
Published: November 2022

Alloy-based materials such as antimony (Sb) are of interest for both Li/Na-ion batteries due to their theoretical capacity and electronic conductivity. Of the various ways to fabricate Sb films (slurry casting, sputtering, etc.) one promising route is through the use of electrodeposition. Electrodeposition is an industrially relevant synthetic technique that allows for the use of solution additives to control different characteristics such as film uniformity, morphology, and electrical conductivity. Solution additives such as cetyltrimethylammonium bromide (CTAB) and bis-(3-sulfopropyl) disulfide (SPS) have been used to control characteristics such as particle morphology, and electrical conductivity in various applications but have not been applied to the electrodeposition of Sb for battery applications. In this study, Sb films were electrodeposited with various concentrations of CTAB and SPS and the structure, morphology, composition, and electrochemical performance in Na-ion batteries were compared. We report that CTAB and SPS additives can significantly influence electrodeposited Sb films by altering the morphology and reducing the crystallinity of the Sb films, affecting the electrochemical performance. These studies provide valuable insight into the tunability of alloy-based films through electrodeposition and solution additives.
The Air Stability of Sodium Layered Oxide Cathodes
Authors: Zuo Wenhua , Xu Guiliang , Amine Khalil
Published: November 2022

Sodium-ion batteries (NIBs) are listed as one of the ideal alternatives for lithium-ion batteries (LIBs), due to the abundant sodium resources, cost-effective electrode materials of NIBs, and same architecture of NIBs to LIBs. To enable the practical implementation of NIBs, advanced cathodes with higher energy/power densities, better safety and cycle life, as well as lower cost are required. Layered lithium transition metal oxides (LiTMO2) are one of the most successful cathode materials for commercial LIBs. Similarly, layered sodium transition metal oxides (NaxTMO2, also termed as sodium layered oxides) are of particular interest for commercial NIBs owing to their high specific capacity, a wide variety of redox-active elements, and the possibility for the manufacturers to employ established synthesis processes as their lithium counterparts.

Sodium layered oxides are built up by ordered stacking of alternate alkali-metal (Na+) layers and transition metal layers (TmO2). The two-dimensional structure makes them the natural hosts for alkali-metal ions and other ions or small molecules, such as H2O. Therefore, when exposed to moist atmospheres, layered oxide materials tend to react with H2O which adsorbed on their surface and thus deteriorate their structure and electrochemical performances. Accordingly, the air-sensitive sodium layered oxides should be well protected from the moist atmospheres, rendering a higher manufacturing and preservation cost.

Here, based on the reaction mechanisms, critical influencing factors, and modification methods of layered oxides in moisture, we try to reach a comprehensive understanding of the air-stability of sodium layered oxides. Moreover, future efforts to resolve the air-stability of sodium layered oxides from Argonne National Laboratory will be also presented.

References

1. Han, M. H.; Gonzalo, E.; Singh, G.; Rojo, T. A comprehensive review of sodium layered oxides: powerful cathodes for Na-ion batteries. Energy Environ. Sci.
2015, 8, 81-102.

2. Zuo, W.; Qiu, J.; Liu, X.; Ren, F.; Liu, H.; He, H.; Luo, C.; Li, J.; Ortiz, G. F.; Duan, H.; Liu, J.; Wang, M. S.; Li, Y.; Fu, R.; Yang, Y. The stability of P2-layered sodium transition metal oxides in ambient atmospheres. Commun.
2020, 11, 3544.

3. Xu, G. L.; Liu, X.; Zhou, X.; Zhao, C.; Hwang, I.; Daali, A.; Yang, Z.; Ren, Y.; Sun, C. J.; Chen, Z.; Liu, Y.; Amine, K. Native lattice strain induced structural earthquake in sodium layered oxide cathodes. Commun.
2022, 13, 436.

4. Zuo, W.; Xiao, Z.; Zarrabeitia, M.; Xue, X.; Yang, Y.; Passerini, S. Guidelines for Air-Stable Lithium/Sodium Layered Oxide Cathodes. ACS Materials Letters
2022, 4, 1074-1086.

5. Fu, F.; Liu, X.; Fu, X.; Chen, H.; Huang, L.; Fan, J.; Le, J.; Wang, Q.; Yang, W.; Ren, Y.; Amine, K.; Sun, S. G.; Xu, G. L. Entropy and crystal-facet modulation of P2-type layered cathodes for long-lasting sodium-based batteries. Commun.
2022, 13, 2826.
Safer and Higher Electrochemical Performance of Binder Free Iron Oxide Anode As an Alternative to Graphite, Silicon and Lithium Metal Anodes in Lithium-Ion Batteries
Authors: Buabeng Emmanuel Ramsey , Noye David Addie
Published: November 2022

Graphite anode has lower capacity, but silicon and lithium metal anodes have higher capacities yet have safety concerns due to volume expansions. The expansion and related safety issues occur during the charging and discharging process and throughout the life of the battery. The objective is therefore to present an alternative that will exhibit desirable properties. We have employed a novel manufacturing technique that involved a new nanostructured material composition, mixing and coating processes to synthesize a nanolayered binder free iron oxide anode. Our experimental results include high electrochemical performance of 1,007mA/g specific capacity and this value remained consistent at various charging and discharging rates. We have demonstrated that our new technique can be used to make higher capacity binder free iron oxide anodes for making lithium-ion batteries for use in increasing range of electric vehicles and electric aircrafts; and increase life span of stationary backup and consumer electronic products. The observed data was derived from using half coin cells, and hence for industrial and commercial applications we plan to test the electrodes in prismatic cells.
Chemo-Mechanical Model of Lithium Dendrite Growth Impacted By External Pressure
Authors: Meyer Julia , Harrison Katharine , Mukherjee Partha P. , Roberts Scott A.
Published: November 2022

The use of lithium metal anodes within commercial batteries is of great interest due to their high energy density and low coulombic efficiency; however, several challenges must be addressed before lithium anodes are implemented in a wide range of applications. Lithium plating and stripping during cell operation leads to the loss of active lithium and the formation of dendrites, which decrease battery capacity and lead to dangerous modes of failure such as fire. Application of external pressure has been shown to mitigate plating to an extent, as it alters the cell morphology and locations of high current density along the anode. In this work we present a 3-D, mesoscale model of lithium plating on an inhomogeneity characteristic of the rough lithium anode surface. The interplay between interfacial growth, state of stress, and ionic transport is explored in a coupled mechanics-electrochemical model. Local stress-induced changes in separator porosity and tortuosity limit bulk and surface ion transport, encouraging Li plating in regions of low stress and contact with liquid electrolyte. The initial electrochemical response across the Li anode surface is studied parametrically with respect to applied pressure, charge rate, and various material properties. The developed finite-element model is then used to simulate plating and stripping by moving the Li surface according to the local reaction rate; the evolution of the interface may thus be studied parametrically. Preliminary results show non-uniform plating across the protrusion that is highly dependent on applied pressure. As the interface evolves, changes in anode-separator contact redirect current and local stresses, leading to various modes of protrusion growth or flattening. This work will provide insight into the modes of protrusion growth based on material properties, applied pressure, and charging rate, and will inform cell design and manufacturing processes in order to mitigate plating and increase battery lifetime and safety.

Supported by the Laboratory Directed Research and Development program at Sandia National Laboratories, a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA-0003525.
Using Synchrotron Techniques, Investigation of Electrochemical Interfaces in Ni-Rich NMC and Sulfide Electrolytes in All-Solid-State Lithium Metal Batteries
Authors: Desta Gidey Bahre Bahre , Hsu (b)* Yao Jane
Published: November 2022

a
Nano-electrochemistry Laboratory, Graduate Institute of Applied Science and Technology, National Taiwan University of Science and Technology, Taipei 106, Taiwan, R.O.C

b
National Synchrotron Radiation Research Center (NSRRC), Hsinchu, 30076, Taiwan, R.O.C

In all-solid-state lithium metal batteries enable long cyclability of high voltage oxides cathode persistent problem for the large scale application as their underprivileged interfacial steadiness in contrast to sulfide solid-state electrolyte. In this context, the interfaces of the solid electrolyte and Ni-rich NMC811 active material are looked upon as interfacial chemical responses induced by delithiation. In this study, we monitor the impedance progress at the unstable electrode|electrolyte interface due to the electrochemical interfacial response and help us understand the complex nature of reactivity and degradation kinetics with the solid-solid interface redox decomposition, which makes decoupling each effect difficult. we investigated the interfacial phenomenon between LPSC and high voltage cathode NMC811. The effects of spontaneous retort by the side of the interface were separated, and the intrinsic electrochemical decomposition of LPSC was quantified. Moreover, we show that the notch of interfacial degradation surges and the presence of oxidation mechanisms. At the higher delithiation stage, the cathode might twitch structural defenselessness and oxygen utter and resulting in further stark degradation. This complex kinetic degradation behavior was investigated at the solid-solid interface in a delithiation NMC811 and SSE based on the local oxidation state of NMC811, and LPSC SE interfacial chemical response. In this work, we used various characterization techniques to investigate the interfacial phenomenon between LPSC|NMC811 combining EIS and advanced synchrotron techniques such as sXAS, XPS, XRF-XANES mapping, and In-situ Raman spectroscopy.

Keywords: delithiation, Ni-rich cathode, Sulfide-solid-state electrolyte, interfacial reaction, Synchrotron XPS, XRF.
(Digital Presentation) High Energy Density Stable Lithium-Sulfur Batteries Enabled By 3D Bilayer Garnet Electrolytes
Authors: Shi Changmin , Takeuchi Saya , Dura Joseph , Wachsman Eric
Published: November 2022

The cubic-garnet (Li7La3Zr2O12, LLZO) Lithium-Sulfur battery (GLSB) shows great promise in the pursuit of achieving high energy densities. The sulfur used in the cathodes are abundant and inexpensive and possess high specific capacity. As well, LLZO displays excellent chemical stability with Li metal. By using unique porous/dense/porous LLZO “trilayer” and dense/porous LLZO “bilayer” architectures developed by our group, an exceptionally high areal current density of 10 mA/cm2 in Li-Li symmetric cells without applied pressure was achieved. However, instability in the sulfur cathode/LLZO interface can cause cell performance issues. Therefore, it is critical to resolve the sulfur cathode/LLZO interfacial challenge to achieve stable cycling.

Here, we created an innovative gel polymer (GPE) buffer layer to stabilize the sulfur cathode/LLZO interface. With a thin bilayer LLZO architecture as a solid electrolyte, stable cycling was achieved with a high initial discharge capacity of 1542 mAh/g corresponding to an energy density of 223 Wh/kg and 769 Wh/L under a discharge current density of 0.87 mA/cm2 without applied pressure. Moreover, the addition of the GPE interlayer also allowed the GLSB cells to maintain an average discharge capacity of 1218 mAh/g over 265 cycles with 80% capacity retention at discharge current density of 1.74 mA/cm2 under a sulfur loading of 5.2 mg/cm2 at 22 (Figure 1). Achieving such stability is a major step in the development of commercial garnet lithium sulfur batteries.

Figure 1
(Digital Presentation) Fabrication of NiO-TiO2 Modified Ni Foam and Its Application As Energy Storage Materials
Authors: Sardar Sukalyan , Rasel Md. , Jamal Mamun
Published: November 2022

Rechargeable batteries are the most effective and efficient devices that store electricity from various intermediate and renewable sources such as solar and wind power. However, the fast-growing market of portable devices requires the use of hybrid materials which ensures safety, high energy density and higher saving for customers [1-3]. In this work, an energy storage device has been fabricated based on novel NiO-TiO2 film modified 3D Nickel Foam (NF) electrode. Simple sol-gel method was used to fabricate the electrode, where NiCl26H2O and TiO2 were used as precursors. 550 °C was used to calcine the NiO-TiO2 modified NF before it can be used as electrode material. During the fabrication process, Ni-Ti ratio has been varied to 1:1 and 1:2 and a comparative study has been developed on the basis of energy storing capacities. In this work, NiO-TiO2 modified Nickel Foam (NiO-TiO2/NF) was used as working electrode, pencil graphite electrode was also used as counter electrode and Ag/AgCl as reference electrode. To calculate the energy storage capabilities, NiO-TiO2/NF was dipped into NaOH and LiCl electrolytes. NiO-TiO2-NF (1:2) shows higher specific capacity in compare to NiO/NF, TiO2/NF and NiO-TiO2-NF (1:1) electrodes. In addition, with the scan rate increases, energy storing capacity of NiO-TiO2-NF found to be decreased. Thereby, a hybrid NiO-TiO2/NF can be used as future electrode material in the energy storage devices.

Acknowledgements

University of Grants Commission of Bangladesh (2021-22) for funding this research.

Reference

N. Padmanathan, et al., J. Mater. Chem. A, 2016, 4, 4820-4830.

J. Islam et al., PLoS ONE, 2021 16(3), e0248142.

M. Jamal et al., Sci. Rep., 2019, 9, 4659.
Flexible Bonding of Polymer Substrates By Microwave Heating of Carbon Nanotubes
Authors: Sohn Minjeong , Kim Min-Su , Ju Byeong-Kwon , Lee Tae-Ik
Published: November 2022

Recently, as research on developing electronic devices for simultaneous implementation of flexibility and conductivity has been continuously conducted, ensuring stable and high reliability of devices in preparation for various mechanical deformation is becoming important. When a physical force such as bending, twisting, or folding is applied, the bonding area between two substrates should ensure stability due to high stress generation. Epoxy resin materials used as standard adhesive agents have brittleness due to the nature of the material, and are weak in terms of flexibility due to increased bonding thickness due to high temperature hardening. In addition, it is difficult to apply as a bonding material in consideration of thermal deformation of the polymer substrate exposed to high temperatures during the process. To improve both flexibility and durability against fatigue deformation, Flexible bonding process is required without adhesive such as epoxy resin with poor brittleness. Surface activation bonding technologies by ion beams and vacuum ultraviolet rays have been developed in previous studies, bonding between plastic substrates by activating thin metal films surface of adhesive layer with ion beam or improving adhesive force by direct-UV radiation on the surface of the polymer substrate. In this study, a flexible bonding process between polymer substrates was developed by heating carbon nanotubes (CNTs) through microwave irradiation. High microwave absorption properties of CNT lead to heat dissipation behavior and light emission characteristics. Heat transfer mechanism of CNT applied to CNT-polymer composites, CNT electrodes fields and has been microwave assisted purification. By utilizing the microwave heating effect, we selected CNT materials for flexible substrates. Multi-walled carbon nanotubes (MWNTs) were coated on a bonded PET polymer substrate and then local heating was performed by microwaves to induce mechanical entanglement between the CNTs and the PET. In the bonding process, the output power of the microwave was adjusted to 600,800 and 1000 Watt, and the bonding strength was evaluated by quantifying the bonding strength was evaluated. For the analysis of the bonding mechanism in the area where mechanical entanglement took place, the CNT-PET bonding interface was analyzed through electron scanning microscope (SEM) measurement, and further analysis was performed for each process condition. In addition, a fracture mechanism analysis that occurred at the junction was performed after the overlapping shear strength test.

Acknowledgments This work was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2020M3H4A3106413, Development of Evaluation Method for Mechanical Deformation of Micro-joints in Micro-LED Module)

Figure 1
(Digital Presentation) Synthesis of Fluorescent Carbon Nanoparticles By Dispersion Polymerization of Acetylene
Authors: Jayswal Vijay Kumar , Ritcey Anna M. , Morin Jean-François
Published: November 2022

Carbon nanoparticles (CNPs) have emerged as one of the most promising nanomaterials due to their distinct optoelectronic properties for a diverse range of applications in the area of electronics, energy conversion/ storage, and bio-imaging. The uniqueness in terms of functions and properties of the CNPs gets more interesting as it changes distinctly with a change in the shape, size, and dimensionality of these nanoparticles. The synthetic methods reported until now involves high-temperature (>100 °C) processes, which often results in uncontrolled shape, size, and polydispersity. In this work, we focus on the development of a low-temperature synthetic method for the preparation of fluorescent carbon nanoparticles allowing precise control over the shape, size, and properties by dispersion polymerization of acetylene as a precursor. The shape- and size-tunable nanoparticles were synthesized in a single step with dispersion polymerization by Glaser-Hay coupling. The shape and size of the resulting carbon nanoparticles are controlled by changing different reaction parameters such as temperature, reaction time and pressure. The control over the different reaction parameters allows us to obtain monodisperse CNPs in spherical (and tubular) shape with a size in the range of 25 nm to 250 nm. The use of low-temperature methods (RT < T < 70 °C) also allows us to overcome the limitations associated with current methods. After isolation, CNPs were characterized by microscopy techniques to analyze their shape and size. The nanoparticles were further characterized to by various techniques for chemical composition, structure, morphology, and optical properties. The residual alkynes in the CNPs' structure were exploited for further post-functionalization/graphitization to yield multifunctional CNPs, which were fluorescent in the blue region.
Development of High Performance CNTs-Based Sensor for Electrochemical Applications
Authors: Osman Abdalghaffar Mohammad
Published: November 2022

This work reports the development of a new robust electrode composed of carbon nanotubes (CNTs) for redox potentiometry to determine ascorbic acid. The electrode was fabricated via catalytic chemical vapor deposition (CVD) of ethylene on Ag substrate in the presence of H2 gas at 800 °C. The C2H2:H2 ratio was 75:90 ml/min respectively. The prepared electrode was characterized with SEM, TEM, XRD, XPS, and Raman spectrometry. SEM showed the formation of aligned CNTs. XRD and Raman spectrometry proved the formation of CNTs with a good degree of graphitization and high crystallinity. XPS analysis results showed 80% of SP2 C–C with a small presence of carbonyls and carboxylates, indicating the high perfection of the CNTs formed. CNT/Ag electrode was applied, for the first time, to zero-current potentiometry and was successfully used to determine ascorbic acid in both pure form and in pharmaceutical formula. Ascorbic acid concentrations down to 0.5 mmol/L was determined. Sigmoidal potentiometric curves were obtained and the results were comparable to those obtained from Pt electrode. The CNT/Ag electrode attained fast equilibrium and exhibited good sensitivity and reproducibility. The enhanced sensing efficiency is attributed to the rapid heterogeneous electron transfer and high electrode surface area offered by CNTs grown via CVD. Additionally, the CVD method produced CNT/Ag electrode with strong adhesion of the CNTs layer to the substrate compared to other CNT-based electrodes prepared by casting the CNTs or mixing them with Nafion. This in turn improves the performance and durability. Moreover, unlike the Pt electrode, the CNT on the surface of this electrode may easily be functionalized by immobilizing the desired moieties via various types of strategies to suit different selective routine applications.

Figure 1
Efficient Electrochemical Oxygen Reduction to Hydrogen Peroxide Production from Nickel-Nitrogen-Doped Mesoporous Graphene Catalyst
Authors: Yeom Kyungbeen , Sung Yung-Eun
Published: November 2022

Hydrogen peroxide(H2O2) is an excellent oxidizing agent with various uses in industrial bleaching, chemical synthesis, and wastewater treatment. Because of its wide range of applications, the global market demand is rapidly increasing. At present, over 95 % of H2O2 is produced through the anthraquinone process which is an environmentally unfriendly process. Therefore, numerous studies have focused on replacing this process for H2O2 with more eco-friendly processes. One of the alternative methods is the electrochemical production of H2O2 through oxygen reduction reaction(ORR), which offers an economical and environmentally friendly route to H2O2.

The oxygen reduction reaction involves a multielectron transfer process in which O2 can be reduced to produce H2O in a four-electron process or undergo a two-electron pathway to form H2O2. However, the design of selective and active electrocatalysts remains a challenge due to competitive reaction pathways between two-electron and four-electron reduction.

We develop 3D mesoporous graphene with high H2O2 production in neutral electrolytes by adjusting the pore size and regulating the atmosphere of Nickel single atom. This catalyst has 3D interconnected hollow N-doped graphene shells and Nickel single atoms will be atomically dispersed on N-doped graphene shells. The mesoporous structure with a large surface area accelerates mass transport. Moreover, electron-poor Nickel atoms yield high selectivity above 90 % and high activity for electrochemical oxygen reduction to produce H2O2 in neutral conditions. This result represents a benchmark for the two-electron ORR electrocatalyst in the neutral conditions.
Rapid Fabrication of Porous Graphene Network Derived Using Photothermal Flash Lamp Processing for High Performance Electrochemical Energy Storage Devices
Authors: Bhardwaj Ayush , Okoroanyanwu Uzodinma , Pande Varun , Watkins James J.
Published: November 2022

Graphene offers superior electrical conductivity and remarkable surface area, which holds great promise for electrochemical energy storage applications including supercapacitors and lithium-ion batteries. Current preparation methods for graphene-like materials require relatively long processing times, extremely high temperatures within controlled atmospheres, and/or involve multi-step reactions that present challenges for high throughput fabrication of graphene-based devices. Moreover, supercapacitor devices fabricated using graphene typically exhibit low areal capacitance, which limits use of the devices. We report a photothermal route to large-scale production of graphene within milliseconds from polymers using high intensity xenon flash lamp on carbon fiber at ambient conditions. The xenon flash lamp provides large-area illumination and a wide emission band (300 nm –1100 nm) that was used to convert the polymeric material directly into graphene upon millisecond exposures. This photothermally heating of polymeric material led to the formation of macroporous few layer graphene-containing network with excellent conductivity, and good adhesion to the carbon fiber all of which facilitate the transport of ions through the material. The fabricated supercapacitor devices exhibited a very high areal capacitance of 200 mF/cm2 at 10 mV/s with retention of more than 70% of its capacitance even after increasing the scan rate to 100 mV/s. Anodes for lithium-ion batteries derived from porous graphene networks on carbon fiber resulted in the device with the performance of 170 mAh/g with mass loading as high as 12 mg/cm2 (including the mass of bare CF). The preparation of high-quality graphene via photothermal pyrolysis of polyaniline is amenable to high throughput processing, enabling large-scale production of electrochemical energy storage devices.