bluuebunny/crossref_metadata_2025_split huggingface dataset:
PEMFC Platinum-Based Catalysts Recycling Using an Electrochemical Process
Authors: Guillet François , Chatenet Marian , Druart Florence , Svecova Lenka , Dubau Laetitia 
Published: November 2022

Hydrogen is one of the most promising energy carriers. Currently, the most used technology to produce electricity from hydrogen, particularly for green mobility, is the technology based on the use of Proton Exchange Membrane Fuel Cells (PEMFC). Platinum, pure or alloyed with another element, remains essential in the design of efficient catalysts either for anode or cathode catalytic layer in PEMFC. This metal is rare and expensive hence recycling it becomes an important issue for the hydrogen sector development.
Chemical ways to recover platinum from PEMFC have been already studied 1-2 based on Pt leaching using either a mix of HCl/HNO3 or HCl/H2O2. In our project, we investigate an electrochemical process to leach platinum contained in aged Pt based catalysts to further resynthesize catalysts from the recovered Pt salts. The electrodissolution of platinum becomes significant with the oxidation of the metal (around 1.1 V vs RHE) but particularly when the oxidized platinum is reduced (around 0.7 V vs RHE) 3. Moreover, the dissolution is enhanced when a complexing agent as chloride anion is introduced 4. The idea of our process is to study the impact of different protocol of steps between high potential (to oxidize platinum) and low potential (to reduce platinum oxide). The improvement of the process is linked to the upper and lower potential values, the number of steps and the nature of the electrolyte and the complexing agent. Our main parameter to monitor the dissolution is the changes in electrochemical real surface area (ECSA) associated to transmission electron microscopy (TEM) images of the catalyst at different stages of the protocol as illustrated in Figure 1.
In terms of methodology a model study on fresh commercial Pt/C catalyst has been first performed to determinate the optimal conditions of Pt dissolution followed by the application of the protocol on membrane electrode assemblies (MEA) aged in real conditions.

1 L. Duclos, L. Svecova, V. Laforest, G. Mandil, et P.-X. Thivel, « Process development and optimization for platinum recovery from PEM fuel cell catalyst », Hydrometallurgy, vol. 160, p. 79-89, mars 2016, doi: 10.1016/j.hydromet.2015.12.013.

2 L. Duclos, M. Lupsea, G. Mandil, L. Svecova, P.-X. Thivel, et V. Laforest, « Environmental assessment of proton exchange membrane fuel cell platinum catalyst recycling », J. Clean. Prod., vol. 142, p. 2618-2628, janv. 2017, doi: 10.1016/j.jclepro.2016.10.197.

3 S. Cherevko, A. R. Zeradjanin, G. P. Keeley, et K. J. J. Mayrhofer, « A Comparative Study on Gold and Platinum Dissolution in Acidic and Alkaline Media », J. Electrochem. Soc., vol. 161, n° 12, p. H822-H830, 2014, doi: 10.1149/2.0881412jes.

4 S. Geiger, S. Cherevko, et K. J. J. Mayrhofer, « Dissolution of Platinum in Presence of Chloride Traces », Electrochimica Acta, vol. 179, p. 24-31, oct. 2015, doi: 10.1016/j.electacta.2015.03.059.

Figure 1
Nitrogen-Doped Carbon Nanosphere Supports for Platinum-Decorated Oxygen Reduction Reaction Catalysts
Authors: Wang Hanson , Ly Alvin , Atanassov Plamen 
Published: November 2022

Carbonaceous materials are widely used as supports for platinum-based oxygen reduction reaction (ORR) catalysts that are prevalent in proton exchange membrane fuel cells (PEMFC). In particular, a variety of carbon blacks are popular due to factors such as commercial availability and high surface area. However, as applications of PEMFCs shift towards heavy-duty vehicle deployment, durability of the supports has become an important criterion when evaluating materials. Carbon support corrosion can lead to Pt nanoparticle detachment and agglomeration, both of which decrease the electrochemically active surface area of the catalyst. Recently, nitrogen-doping of carbon supports has shown promising results towards improving stability in fuel cell operating conditions1. Graphitization is another strategy that mitigates carbon corrosion, as graphitic carbon is more resistant to oxidation than amorphous carbon2. In this work, we present a set of nitrogen-doped carbon nanosphere supports obtained via a one-pot colloidal synthesis and then decorated with Pt nanoparticles for ORR catalysis (Pt/NCS). The nitrogen-doped supports are monodispersed, contain a mesoporous pore structure, and show a higher level of bulk graphitization than commercial carbon blacks. Our work also elucidates how differences in certain nitrogen moieties on the carbon support’s surface impact catalytic activity. The Pt/NCS catalysts exhibit similar mass activity and improved specific activity in rotating disk electrode measurements compared to a commercial Pt/C catalyst at similar Pt weight loadings.
(1) Ott, S.; Orfanidi, A.; Schmies, H.; Anke, B.; Nong, H. N.; Hübner, J.; Gernert, U.; Gliech, M.; Lerch, M.; Strasser, P. Ionomer Distribution Control in Porous Carbon-Supported Catalyst Layers for High-Power and Low Pt-Loaded Proton Exchange Membrane Fuel Cells. Nat. Mater.
2020, 19 (1), 77–85.
(2) Yu, P. T.; Gu, W.; Zhang, J.; Makharia, R.; Wagner, F. T.; Gasteiger, H. A. Carbon-Support Requirements for Highly Durable Fuel Cell Operation. In Polymer Electrolyte Fuel Cell Durability; Büchi, F. N., Inaba, M., Schmidt, T. J., Eds.; Springer New York: New York, NY, 2009; pp 29–53.
Using 2D-Phthalocyanine Metal Organic Framework-Based Catalysts for Oxygen Reduction Reaction in Alkaline Media
Authors: Wei Lingze , Chen Gan , Hossain Md Delowar , Zamora Zeledon Jose Andres , Kreider Melissa E , Stevens Michaela Burke , Bajdich Michal , Bao Zhenan , Jaramillo Thomas F 
Published: November 2022

Developing high performance electrocatalysts to improve the sluggish kinetics of oxygen reduction reaction (ORR) at the cathode is essential in expanding fuel cell applications. Metal organic frameworks (MOFs), given their high surface area, tunable pore size, and diverse metal choices, are promising candidates to catalyze such a reaction. Herein, we report a family of nine 2D-phthalocyanine MOF-based catalysts for alkaline ORR, where M = Co, Ni, Cu. Structurally, these bimetallic materials have two distinct metal sites, where M1 is a phthalocyanine moiety and M2 is a node, existing as M-N4 moiety. X-ray Diffraction (XRD) shows that all as-prepared MOFs have similar structures and inter-layer spacing. X-ray Photoelectron Spectroscopy (XPS) shows slight shifts in binding energy when the same element is placed in a M1 or M2 site, which indicates that the M1 and M2 sites are chemically distinct.
Through cyclic voltammetry we evaluate the role of the metal sites for ORR activity and selectivity in 0.1 M KOH. All materials are active for alkaline ORR, while Ni (M1) – Co (M2) has the best overall kinetic activity performance of - 5 mA cm-2 at 0.7 V vs. RHE. Cu – Cu, on the other hand, is the least active combination under the same testing conditions. Within composition series where M2 = Co, the activity trend for M1 is Ni > Cu ~ Co. From a 2-electron selectivity perspective, M1 = Ni > Cu > Co. From these general trends we hypothesize that Co M2 and Ni M1 sites are essential in promoting 4- and 2-electron selectively, respectively. On average we find a nominal ORR performance trend where M2 = Co > Cu > Ni. Interestingly, we note that the M1 identity also plays a non-linear role in activity and selectivity modulation. Though we identify one of the metal sites (M1 or M2) as the dominating site for activity and/or selectivity, the other site also contributes to the total performance. The density functional theory (DFT) calculation supports our experimental results and finds out that Ni as M1 is highly selective for H2O2 formation whereas Co as M2 shows excellent activity for ORR. Our predicted volcano plot shows that MOF with Ni – Co and Cu – Co combinations at Co active site offering lowest ORR overpotential among all other combinations, which is also in good agreement with experimental findings.
By evaluating different metal sites performance through electrochemical testing, we can better understand the active species in the MOF catalytic system. By pairing theory with experiment, we gain active site insight to design new specific enhanced active motifs. We believe that these performance trends can assist in better designing efficient MOF-based ORR catalysts that can lead to advances in clean energy technology for sustainable development.
Electrochemically Dealloyed 3D Porous Copper Nanostructure As High-Performance Anode Current Collector of Li-Metal Batteries
Authors: Ma Yifan , Zhang Guangxing , Ma Xuetian , Liu Zhantao , Chen Hailong 
Published: November 2022

Li metal anode is the ultimate choice for Li batteries owning to its highest theoretical capacity (3806 mAh/g) and lowest redox potential (-3.04 V vs. standard hydrogen electrode) among possible candidates.[1] However, despite the advantages of Li metal anodes, a number of remaining challenges must be addressed before its commercialization: undesired dendrite growth of Li, and irreversible parasitic reactions between Li and electrolyte, etc.
Stabilization of Li metal is essential for commercial application of Li metal anodes. In the past few years, several strategies have been developed to suppress Li dendrite growth and stabilize SEI formation during Li plating/stripping processes. Among these strategies, 3D current collectors showed its high potential in Li anode stabilization due to its much larger surface area, which can provide much more Li nucleation sites, alleviate volumetric changes of Li anode, and decrease practical current density. Thus, compared to flat Cu foil used in commercial Li-ion batteries, 3D Cu current collectors can facilitate uniform Li deposition, mitigate Li dendrite growth, and enhance Li cycling stability.[2]
Our previous work reported a 3D porous Cu current collector fabricated via a facile one-step electrodeposition method directly on commercial Cu foil. [3] The fabricated 3D porous Cu current collector showed stable long-term cycling with a high areal capacity of 6 mAh/cm2 and no Li dendrite growth was observed during cycling process. However, for the one-step electrodeposition method, the thickness of the porous Cu deposition layer is limited. Thus, preparation of 3D porous Cu layers with both high thickness and high porosity is necessary to further improve the areal capacity of this current collector. Recently, we developed a new two-step electrochemical process to fabricate thick and porous Cu layer: a thick Cu-Zn alloy was first electrodeposited on commercial Cu foil, and Zn was then removed electrochemically, leaving a thick and highly porous 3D Cu layer. Compared to our previous method, this 3D Cu layer has a high thickness of ~14 um and porosity of ~72%. This new 3D Cu current collector can achieve stable Li cycling up to 230 h at high areal capacity of ~10 mAh/cm2 at a high current density of 10 mA/cm2, demonstrated its high commercial application potential in Li-metal batteries.

Tarascon, J.M. and M. Armand, Issues and challenges facing rechargeable lithium batteries. Nature, 2001. 414(6861): p. 359-367.

Yang, C.P., et al., Accommodating lithium into 3D current collectors with a submicron skeleton towards long-life lithium metal anodes. Nature Communications, 2015. 6.

Ma, X., Z. Liu, and H. Chen, Facile and scalable electrodeposition of copper current collectors for high-performance Li-metal batteries. Nano Energy, 2019. 59: p. 500-507.
Insights into the Na-Alloying Mechanism and Zintl Phase Transition of Lead-Based Anodes
Authors: Park Jehee , Han Jinhyup , Gim Jihyeon , Bak Seongmin , Ahmed Shabbir , Iddir Hakim , Garcia Juan , Kim Youngsik , Lee Eungje , Johnson Christopher S. 
Published: November 2022

Sodium-ion batteries (SIBs) has been received growing attention in the electrical energy storage fields due to their low cost and earth-abundant sodium. [1] However, there has been a lack of new discoveries, growth directions, and real advancement with respect to Na-storage anodes. Despite the chemical similarities between sodium and lithium as alkali elements, the larger Na ion than Li ions (ionic radii of 0.98 Å and 0.68 Å, respectively) is limited to insertion into host materials and results in different phase transition behavior. [2] Among the available anode candidate materials for SIBs, lead (Pb), which has a large atomic size than other elements (e.g. Si, Sn), provides a big interstitial space to accommodate large Na ions by fast ionic diffusion, enabling reversible Na alloying/dealloying and exhibiting high volumetric capacity. [3] Furthermore, when Pb is used as anode with layered sodium transition metal oxide as cathode, the energy density of the pouch-type cell is estimated to be 549 Wh/L and the cost is lower than 63.5 USD/kWh according to the Argonne BatPac model. [4] Therefore, Pb-based materials have competitive potential as promising anodes and it is crucial to understand the electrochemical process from a fundamental perspective.
Here, we investigate a unique Na storage mechanism using a novel Pb-based carbon nanocomposite anode synthesized by a simple high-energy milling method. The electrochemical data show a decent cycle performance with a reversible capacity of 381 mAh/g. Nevertheless, the Na-storage performance of the Pb-based anode was not attractive compared to Li cells. In-situ X-ray diffraction and ex-situ X-ray absorption spectroscopy reveal the reaction mechanism and Zintl-phase formation that limits the Na storage, unlike the Li reaction. We expect these findings provide fundamental knowledge of Na-alloying reaction and guidance for designing anode materials for high-performance SIBs.
[1] K. Kubota and S. Komaba Journal of The Electrochemical Society, 2015, 162 (14) A2538-A2550
[2] M. Lao, Y. Zhang, W. Luo, Q. Yan, W. Sun, and S. X. Dou Adv. Mater. 2017,
29
, 1700622
[3] Chia-Yun Chou, Myungsuk Lee, and Gyeong S. Hwang, J. Phys. Chem. C 2015, 119, 27, 14843–14850
[4] P. Nelson, K. Gallagher, I. Bloom, Dennis Dees, and Shabbir Ahmed, BatPaC, Argonne National Laboratory. http://www.cse.anl.gov/batpac.
PGM-Free Catalysts and Electrodes for Anion Exchange Membrane Water Electrolyzers
Authors: Osmieri Luigi , He Yanghua , Yu Haoran , Cullen David A. , Zelenay Piotr 
Published: November 2022

Recent progress in the development of anion exchange membranes (AEMs) with improved performance and durability has opened the way for the application of the AEM-based electrolyzers in low-temperature water electrolysis (LTWE),1 an important technology for producing “green” hydrogen.2 AEM-LTWEs can potentially operate on pure water, i.e., without highly concentrated and corrosive supporting electrolyte, and they allow for replacement of electrocatalysts based on platinum group metals (PGMs) with PGM-free ones, thus addressing the main drawbacks of the liquid-alkaline (LA) and proton exchange membrane (PEM) electrolyzers.3 Consequently, the development of PGM-free electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline media is of primary importance for the deployment of AEM-LTWEs that has attracted significant attention of researchers.4–6 Besides improving the catalytic activity, the integration of PGM-free HER and OER electrocatalysts into electrodes for operation in AEM electrolyzers is crucial to achieving satisfactory electrolyzer performance and making them competitive with the LA and PEM systems.7,8

In this work, we measured electrocatalytic activity of a series of OER and HER catalysts in a three-electrode cell and then implemented these catalysts in electrodes for testing in an AEM electrolyzer. We investigated different classes of OER catalysts, including commercial IrO2 (a PGM ORR benchmark), LaxSr1-xCoO3-δ oxides, Ni-Fe nanofoam oxides, Ni-Fe aerogel-derived oxides, and MOF-derived Co oxides. In the HER-catalyst part of the study, we compared a commercial PtRu/C (a PGM HER benchmark) with an aerogel NiMo/C catalyst. Catalysts and electrodes before and after testing were characterized by XRD, SEM, EDS, and XPS.
In addition to exploring different catalysts, we investigated the impact of several fabrication variables such as the ink deposition method, amount of ionomer, incorporation of a binding agent, and the type of anode porous transport layer on performance. The tests were carried in an electrolyzer operating with pure water and two electrolyte solutions, 0.1 M KOH and 1% K2CO3. The results show that, in addition to the OER and HER electrocatalytic activity, the electrode fabrication is an important factor affecting AEM electrolyzer performance, especially in the pure-water operation mode, in which case assuring an effective transport of the OH– ions within the catalyst layer is especially challenging.

References

Y. S. Kim, ACS Appl. Polym. Mater. (2021).

C. Santoro et al., ChemSusChem, 202200027 (2022).

H. A. Miller et al., Sustain. Energy Fuels, 4, 2114–2133 (2020).

D. Xu et al., ACS Catal., 9, 7–15 (2019).

H. Shi et al., Adv. Funct. Mater., 2102285, 1–10 (2021).

H. Doan et al., J. Electrochem. Soc., 168, 084501 (2021).

N. U. Hassan, M. Mandal, B. Zulevi, P. A. Kohl, and W. E. Mustain, Electrochim. Acta, 409, 140001 (2022).

G. A. Lindquist et al., ACS Appl. Mater. Interfaces (2021).
3D-Structured Porous Carbon Host with Iron Nanoparticles for High Performance Sodium-Metal Batteries
Authors: Lee Kyungbin , Lee Young Jun , Kim Bumjoon J , Lee Seung Woo 
Published: November 2022

Sodium (Na)-metal batteries have emerged as a promising alternative to lithium-metal batteries for next-generation batteries due to the low cost and natural abundance of Na. However, high reactivity of Na metal and uncontrollable growth of Na dendrites hinder the safe operation of Na-metal batteries. Several studies have been conducted to resolve those problems and regulating the initial Na nucleation is one of the promising methods for dendrite-free Na-metal anodes. Previous studies reveal that sodiophilic metal nanoparticles (Au, Ag, Sn, Sb, etc.) embedded 3D structures can induce the homogeneous initial Na nucleation and further guide uniform Na deposition. Herein, we newly develop a 3D nanostructured porous carbon particle containing carbon-shell-coated Fe nanoparticles (PC-CFe) as a highly reversible Na-metal host.1 PC-CFe delivers excellent cycling stability in asymmetric cells over 500 cycles with an average Coulombic efficiency of 99.6% at 10 mA cm-2 with 10 mAh cm-2 and in symmetric cells over 14,400 cycles at 60 mA cm-2. The role of carbon coating on Fe nanoparticles for enhanced sodiophilicity is also investigated by DFT calculations. Furthermore, the anode-free Na-metal batteries with a PC-CFe host and a high-loading Na3V2(PO)4 cathode shows an excellent capacity retention of 97% after 100 cycles at 1 mA cm-2. This work provides a novel approach toward the rational design of 3D hosts for next-generation Na-metal batteries.
References:
1. Lee, K.; Lee, Y. J.; Lee, M. J.; Han, J.; Lim, J.; Ryu, K.; Yoon, H.; Kim, B.-H.; Kim, B. J.; Lee, S. W. A 3D Hierarchical Host with Enhanced Sodiophilicity Enabling Anode-Free Sodium-Metal Batteries. Adv. Mater.
2022, 34, 2109767.
Thermal Stability of Active Materials Versus Different Type of Electrolytes
Authors: Hsu Hungjen , Lu Yushi , Ünal Mahir , Körber Nico , Chang Hansen , Frey Martin , Garche Jürgen 
Published: November 2022

The safety of Lithium ion battery (LIB) is recently a hot topic due to their increased use by the electric vehicles. Energy density has become more and more important to solve the range anxiety. However, thermal behavior becomes more unstable due to this increase in energy density. Several studies have claimed that the main reason batteries have thermal runaway events are the reactions between the intercalated lithium in the anode and the liquid electrolytes [1] [2]. Therefore, solid state electrolytes are proposed [3] [4] to be an option to increase the thermal stability of LIBs.
In this work, thermal evaluation of Solid state battery materials will first be defined by a differential scanning calorimeter to understand the thermal stability of the different materials that might be used in different types of solid state cells. Materials tested include layered oxide cathodes with different Ni content, pure lithium metal and several types of solid electrolytes such as sulfides, polymers and oxides. Heat flow test with different combinations of the materials, such as cathode with anode, cathode with electrolytes and anode with electrolytes were conducted to isolate reaction mechanisms between the different materials. The results show, that compared to the thermal runaway paths of cell with liquid electrolytes, sulfide and oxide electrolytes show the possibility of improved thermal stability. However, polymer electrolytes might have the similar, or even worse, thermal behavior as liquid electrolytes.
Reference
[1] Ren, X. Feng, L. Liu, H. Hsu, L. Lu, L. Wang, X. He and M. Ouyang. "Investigating the relationship between internal short circuit and thermal runaway of lithium-ion batteries under thermal abuse condition." Energy Storage Materials, 2021.
[2]Mukai, T. Inoue and K. "Are All-Solid-State Lithium-Ion Batteries Really Safe?−Verification by Differential Scanning Calorimetry with an All-Inclusive Microcell." ACS Applied Materials & Interfaces, 2016.
[3]Chen, A. M. Nolan, J. Lu, J. Wang, X. Yu, Y. Mo, L. Chen, X. Huang and H. Li. "The Thermal Stability of Lithium Solid Electrolytes with Metallic Lithium." Joule, 2020.
[4]Feng, M. Ouyang, X. Liu, L. Lu, Y. Xia and X. He. "Thermal runaway mechanism of lithium ion battery for electric vehicles: A review." Energy Storage Materials, 2018.

Figure 1
Highly Reversible Zn Metal Anode Enabled by Sustainable Hydroxyl Chemistry
Authors: Ma Lin , Vatamanu Jenel , Hahn Nathan T , Pollard Travis , Schroeder Marshall , Petkov Valeri , Ding Michael , Ren Yang , Luo Chao , Allen Jan L , Wang Chunsheng , Xu Kang 
Published: November 2022

Enhancing Zn anode reversibility with sustainable chemistries is urgent for unlocking rechargeable Zn metal battery technology to complement Li-ion batteries and meet the growing demand for sustainable energy storage. However, conventional practices in electrolyte design which address anode irreversibility through altering the Zn2+ solvation shell often rely on costly concentrated chemicals1-2.
In this work, we demonstrate a sustainable and cost-effective electrolyte design strategy by using methanol as a solvent exemplar. The designed electrolyte exhibits unprecedented Zn reversibility combined with high depth of discharge (Coulombic efficiency (CE) >99.5% with 50% Zn utilization and a dendrite-free behavior >1800h) at 25°C due to the determinant interphasial chemistries enabled by the hydroxyl group. Moreover, the Zn anode also shows a high CE >99.5% with 20% Zn utilization at -40°C when supported by a desirable electrolyte bulk transport property. Excellent performance is demonstrated in the Zn || metal-free organic cathode full cells in a wide temperature range. The microscopic characterization and modeling identify the mechanism of unique interphase chemistry and its functionalities as the key factors responsible for dictating reversible Zn chemistry.
Reference

E. Blanc, D. Kundu, L. F. Nazar, Joule
2020, 4, 771–799.

Ma, M. A. Schroeder, O. Borodin, T. P. Pollard, M. S. Ding, C. Wang, K. Xu, Nature Energy
2020, 5, 743-749.