Article
Chemistry, Physical
Leandro Gonzalez Rodriguez, Roberto Campana Prada, Margarita Sanchez-Molina, Tonatiuh Alejandro Rodriguez Victoria
Summary: The electrochemical performance of MEAs with ultra-low platinum load and different compositions of Nafion/C was investigated. Results showed that using oxygen as an oxidant gas can increase power density, while the electrode with 40 wt% Nafion/C exhibited the most uniform ionomer network surface.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Ambroz Kregar, Matija Gatalo, Nik Maselj, Nejc Hodnik, Tomaz Katrasnik
Summary: Mathematical modelling is crucial for understanding the degradation of platinum-based carbon-supported catalysts in PEMFC, helping in the development of new materials and mitigation strategies, as well as improving the understanding of individual degradation mechanisms. According to the model, platinum dissolution and redeposition are strongly affected by temperature, being the main mechanism of particle growth at temperatures below 60 degrees C.
JOURNAL OF POWER SOURCES
(2021)
Article
Electrochemistry
Michael Moore, Shantanu Shukla, Stephan Voss, Kunal Karan, Adam Weber, Iryna Zenyuk, Marc Secanell
Summary: The study presents a single-phase model for proton exchange membrane fuel cells, involving hydrogen transport, hydrogen oxidation reaction, and oxygen reduction reaction. Experimental results demonstrate that the model can effectively predict changes in OCV with varying platinum loading and fuel cell performance. At low platinum loadings, unreacted hydrogen escapes due to oxide blocking and anion adsorption, highlighting the kinetic limitations of the hydrogen oxidation reaction.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2021)
Article
Engineering, Environmental
C. F. Zinola
Summary: An analytical solution of the water mass balance equation considering diffusion and electroosmotic drag fluxes was obtained. The experimental results showed that the operating conditions significantly affected the performance of the fuel cell, and continuous water recycling could preserve the performance stability of the fuel cell.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Haruhiko Shintani, Nobuhiro Miyata, Yasushi Sugawara
Summary: The study found that the particle size of mesoporous carbons significantly affects the performance of catalysts in polymer electrolyte fuel cells, with the optimal polarization performance achieved at a particle size of 695 nm. The oxygen reduction reaction activity of Pt/MPCs increases with the size of the mesoporous carbon particles, and the internal structure also significantly impacts the activity.
JOURNAL OF POWER SOURCES
(2021)
Article
Energy & Fuels
Qiuxiang Lu, Shenfu Yuan, Xianyang Wang, Yanwei Zhao, Xiaoguang Xie, Hui Liu, Jinchang Liu
Summary: The addition of WS@5 Fe catalyst significantly affects the distribution of products during biomass pyrolysis and volatile reforming reactions, leading to a decrease in char and heavy oil yield. In addition, carbon deposition on the catalyst is mainly attributed to the wrapping and covering of Fe by coke during the catalyst cycle process.
Article
Chemistry, Applied
Eleonora Vottero, Michele Carosso, Riccardo Pellegrini, Monica Jimenez-Ruiz, Elena Groppo, Andrea Piovano
Summary: In this article, the behavior of activated carbon and Pt and Pd catalysts in the presence of H2 was investigated using Inelastic Neutron Scattering (INS) spectroscopy. The INS spectra provided detailed information about H2 physisorption and the formation of metal hydrides upon hydrogenation. The occurrence of hydrogen spillover from the metal nanoparticles onto the activated carbon was also observed. Overall, this work provides important insights for better understanding the complex interaction between H2 and Pt and Pd-loaded activated carbon catalysts.
Article
Materials Science, Multidisciplinary
Yunqin Hu, Linlin Xiang, Long Kuai, Yanyan Zhao, Sufeng Cao, Li Liu, Caihong Fang, Baoyou Geng
Summary: This research establishes a new method of incipient wetness impregnation (IWI) for preparing high-loading Pt/C catalysts with sub-3 nm Pt nanoparticles and a loading up to 60 wt%. A two-step reduction strategy is developed to overcome the limitations of traditional IWI method in controlling the size of Pt nanoparticles at high loadings. The as-prepared 60% Pt/C catalyst exhibits high power density and low Pt loading, outperforming the state-of-the-art commercial 60% Pt/C in H-2-air fuel cells.
ACS MATERIALS LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Q. Liu, P. Rzepka, H. Frey, J. Tripp, A. Beck, L. Artiglia, M. Ranocchiari, J. A. van Bokhoven
Summary: This study investigates the sintering behavior of supported metal nanoparticles and finds that the sintering rate is accelerated when the interparticle distance is shortened. Enlarging the interparticle distance and using surface overcoating techniques can improve the resistance to sintering.
MATERIALS TODAY NANO
(2022)
Article
Chemistry, Physical
Lu Lu, Han Deng, Zhipeng Zhao, Bing Xu, Xin Sun
Summary: In this study, N-doped carbon nanotube supported Pt nanowire catalysts were successfully synthesized and their electrocatalytic activity and durability in proton exchange membrane fuel cells were investigated. The PtNW/NCNTs demonstrated better oxygen reduction reaction activity and stability, showing promise as an alternative to traditional Pt/C catalysts.
JOURNAL OF POWER SOURCES
(2022)
Article
Chemistry, Multidisciplinary
Yongping Luo, Wei Zhong, Ping Huang, Hui Ou, Haiyan Fu, Chen Liu, Zonghu Xiao, Shunjian Xu
Summary: Utilizing core-shell CMs@NiO as the support material, the enhancement of electrocatalytic oxidation of methanol by Pt catalyst was achieved, showing improved activity and stability, which has potential applications.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Applied
Yibing Cai, Takeshi Matsumoto, Shuhei Yasuda, Shunsuke Yamada, Yin Liu, Yunan Wang, Peipei Xiao, Junko N. Kondo, Toshiyuki Yokoi
Summary: Three-dimensional porous carbon was prepared using a hard templating method with monodispersed silica nanospheres. Platinum nanoparticle catalyst on the prepared carbon was obtained via a liquid-phase method. The influence of pore structure and morphology of the replicated porous carbon supports on the Pt catalyst was investigated by applying it in the C-methylation reaction.
Article
Energy & Fuels
Wojciech Kicinski, Slawomir Dyjak, Mateusz Gratzke, Wojciech Tokarz, Artur Blachowski
Summary: Fe-N-C electrocatalysts were prepared by pyrolysis of N- or N/S co-doped synthetic polymers with FeCl3, and the influence of sulfur and phenanthroline additives on their performance in fuel cells was studied. The results showed that the specific micro-colloidal morphology of the carbon gel-based materials dominated the catalysts' and the final CCLs' performances.
Article
Chemistry, Physical
M. Ahsanul Haque, A. Bakar Sulong, L. Kee Shyuan, E. Herianto Majlan, T. Husaini, R. Emilia Rosli
Summary: The polymer/MWCNT nanocomposites synthesized in this study exhibited higher specific surface areas compared to the pristine MWCNT. The MEAs fabricated using hot pressing method showed a maximum power density of 112.10 mW/cm(2) in a single cell. The synthesized catalyst-supporting materials enhanced electrochemical activity and stability, achieving the main objective of this study.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Jochen Schuetz, Heike Stoermer, Patrick Lott, Olaf Deutschmann
Summary: The study reveals that aging catalysts leads to a decline in catalytic activity due to particle sintering, and bimetallic catalysts undergo morphological changes during hydrothermal treatment, transforming from core-shell structures to heterogeneous agglomerates.
Article
Chemistry, Physical
Dayton G. Kizzire, Alexander M. Richter, David P. Harper, David J. Keffer
Summary: This study uses reactive molecular dynamics simulations to investigate and compare the binding mechanisms of lithium and sodium ions in nanostructured carbon composite anodes. The results show that lithium ions preferentially bind at the interface between amorphous and crystalline domains, while sodium ions preferentially bind in the crystalline domain. This difference in binding mechanisms is explained through a comparison of binding energies in the carbon composite to the energies of the respective metals and metal hydrides.
MOLECULAR SIMULATION
(2021)
Article
Physics, Multidisciplinary
Donald M. Nicholson, C. Y. Gao, Marshall T. McDonnell, Clifton C. Sluss, David J. Keffer
Summary: This study demonstrates that within the class of pair potential Hamiltonians, the excess entropy is a universal, temperature-independent functional of density and pair correlation function, extending Henderson's theorem. The Kirkwood approximation is applied to both fluids and solids, leading to the development and comparison of approximate excess entropy functionals with results from thermodynamic integration.
Article
Chemistry, Multidisciplinary
Lu Yu, Chien-Te Hsieh, David J. Keffer, Hao Chen, Gabriel A. Goenaga, Sheng Dai, Thomas A. Zawodzinski, David P. Harper
Summary: An efficient chemical-wet method was used to construct a three-dimensional carbon composite as an electrode material for supercapacitors. Adding carbon dots significantly improved the surface affinity of the electrode towards aqueous electrolytes, leading to increased capacitance and enhanced cycle stability of the supercapacitors.
Article
Computer Science, Interdisciplinary Applications
Adam Spannaus, Kody J. H. Law, Piotr Luszczek, Farzana Nasrin, Cassie Putman Micucci, Peter K. Liaw, Louis J. Santodonato, David J. Keffer, Vasileios Maroulas
Summary: The utilization of materials fingerprinting process allows for extracting unprecedented structural information from APT datasets, even in the presence of noise and sparsity, to accurately classify the lattice structure of materials.
COMPUTER PHYSICS COMMUNICATIONS
(2021)
Article
Energy & Fuels
Bernadette R. Cladek, S. Michelle Everett, Marshall T. McDonnell, Dayton G. Kizzire, Matthew G. Tucker, David J. Keffer, Claudia J. Rawn
Summary: The presence of CO2 in mixed hydrates increases the stability range and creates a barrier for CH4 to completely leave the structure. When CH4 and CO2 co-occupy the hydrate, the host structure is more strongly distorted than in pure CH4 and CO2 hydrates, but this effect diminishes with increasing temperature.
Article
Chemistry, Multidisciplinary
Dayton G. Kizzire, Alexander M. Richter, David P. Harper, David J. Keffer
Summary: The study shows that hard carbons have high diffusion rates and ion storage mechanisms, which are greatly influenced by nanostructures.
Article
Chemistry, Multidisciplinary
Valerie Garcia-Negron, Stephen C. Chmely, Jan Ilavsky, David J. Keffer, David P. Harper
Summary: This study investigated the thermochemical conversion of lignin powders from different feedstocks using X-ray scattering techniques. The results showed that the carbonization temperature affects the crystallinity and morphological features of the carbon. Softwoods and switchgrass were found to be viable substitutes for graphite and can be used to produce application-specific materials.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Dayton G. Kizzire, Valerie Garcia-Negron, David P. Harper, David J. Keffer
Summary: This study investigates the radial distribution functions (RDFs) of lignin-based carbon composites (LBCCs) using synchrotron X-ray and neutron scattering, and proposes a Hierarchical Decomposition of the Radial Distribution Function (HDRDF) modeling method to characterize the local atomic environment and develop quantitative Process-Structure-Property-Performance (PSPP) relationships. The PSPP relationships for LBCCs defined in this work include the dependence of crystallite size on lignin feedstock and the increase of crystalline volume fraction, nanoscale composite density, and crystallite size with increasing reduction temperature.
Article
Materials Science, Multidisciplinary
Alexander D. Greenhalgh, Liurukara D. Sanjeewa, Piotr Luszczek, Vasileios Maroulas, Orlando Rios, David J. Keffer
Summary: The study reports the use of FCRDF analysis to evaluate atomic ordering in crystal structures and considers spatial uncertainty and atomic abundance when processing APT data sets. Applying this method to samples such as Ni3Al and Al1.3CoCrCuFeNi helps observe atomic ordering and elemental segregation phenomena.
FRONTIERS IN MATERIALS
(2021)
Article
Physics, Multidisciplinary
Clifton C. Sluss, Jace Pittman, Donald M. Nicholson, David J. Keffer
Summary: Evaluation of entropy from molecular dynamics simulation remains challenging. A recent study demonstrated a functional based on pair correlation function that can accurately determine excess entropy. This research explores the general applicability of this method and applies it to three different materials.
Article
Energy & Fuels
Lu Yu, Kendhl Seabright, Ishan Bajaj, David J. Keffer, David M. Alonso, Chien-Te Hsieh, Mi Li, Hao Chen, Sheng Dai, Yasser Ashraf Gandomi, Christos T. Maravelias, David P. Harper
Summary: In this study, lignins extracted from yellow pine and switchgrass were converted into porous activated carbon electrodes for high energy-density supercapacitors. The research explores the impact of lignin composition on the structure and electrochemical properties of activated carbons. The resulting electrodes exhibited excellent stability and efficiency.
FRONTIERS IN ENERGY RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Leo Zella, Jaeyun Moon, David Keffer, Takeshi Egami
Summary: Metallic glasses exhibit fast mechanical relaxations known as nearly constant loss (NCL) at temperatures below the glass transition. Through molecular dynamics simulations, it is found that NCL relaxation is due to transient groups of atoms that revert to typical atomic-level viscoelastic behavior. These groups of atoms are homogeneously distributed throughout the glass, without any outstanding features.
Article
Engineering, Chemical
Lu Yu, David J. Keffer, Chien-Te Hsieh, Jakob R. Scroggins, Hao Chen, Sheng Dai, David P. Harper
Summary: This study develops a recyclable adsorbent for the large-scale environmental remediation of polluted water. The adsorbent is produced from an abundant, low-cost, and renewable feedstock via a simple processing procedure. The experimental results demonstrate that the adsorbent has high adsorption performance, high regeneration efficiency, economic and environmental viability, single-step processing, and large-scale production.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Energy & Fuels
Bernadette R. Cladek, A. J. Ramirez-Cuesta, S. Michelle Everett, Marshall T. McDonnell, Luke Daemen, Yongqiang Cheng, Paulo H. B. Brant Carvalho, Christopher Tulk, Matthew G. Tucker, David J. Keffer, Claudia J. Rawn
Summary: Natural hydrate deposits are a rich source of CH4. Recent studies have shown that CH4 can be extracted from hydrates by CO2 exchange, which also has the potential for carbon sequestration. Understanding the impact of guest variation in CH4, CO2, and mixed hydrates on their stability and the processes of methane extraction and CO2 sequestration is crucial. The use of inelastic neutron scattering has revealed the dynamic modes in hydrate structures and the behavior of CH4, providing valuable insights for further research.
Article
Chemistry, Physical
Michael T. T. Broud, Mohsen Samandari, Lu Yu, David P. P. Harper, David J. J. Keffer
Summary: Mitigating the extreme effects of climate change caused by fossil fuel burning requires global carbon sequestration. Carbon quantum dots (CQD) are evaluated as materials for selective carbon dioxide adsorption. CQDs can selectively adsorb CO2 from gas mixtures and the selectivity depends on their size, composition, and modification. This preliminary computational study provides a framework for optimizing CQD atomic architecture on a CQD/AC adsorbent.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Tianyu Chen, Zhibin Lu, Guangjin Zeng, Yongmin Xie, Jie Xiao, Zhifeng Xu
Summary: The study introduces a high-performance LSGM electrolyte-supported tubular DC-SOFC stack for portable applications, which shows great potential in developing into high-performing, efficient, and environmentally friendly portable power sources for distributed applications.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Wenbin Tong, Yili Chen, Shijie Gong, Shaokun Zhu, Jie Tian, Jiaqian Qin, Wenyong Chen, Shuanghong Chen
Summary: In this study, a three-dimensional porous NiO interface layer with enhanced anode dynamics is fabricated, forming a Schottky contact with the zinc substrate, allowing rapid and uniform zinc plating both inside and below the interface layer. The resulting NiO@Zn exhibits exceptional stability and high capacity retention.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Yafeng Bai, Kaidi Li, Liying Wang, Yang Gao, Xuesong Li, Xijia Yang, Wei Lu
Summary: In this study, a flexible zinc ion supercapacitor with gel electrolytes, porous alpha-MnO2@reduced graphene oxide cathode, and activated carbon/carbon cloth anode was developed. The device exhibits excellent electrochemical performance and stability, even at low temperatures, with a high cycle retention rate after 5000 cycles.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Anmol Jnawali, Matt D. R. Kok, Francesco Iacoviello, Daniel J. L. Brett, Paul R. Shearing
Summary: This article presents the results of a systematic study on the electrochemical performance and mechanical changes in two types of commercial batteries with different anode chemistry. The study reveals that the swelling of anode layers in batteries with silicon-based components causes deformations in the jelly roll structure, but the presence of a small percentage of silicon does not significantly impact the cycling performance of the cells within the relevant state-of-health range for electric vehicles (EVs). The research suggests that there is room for improving the cell capacities by increasing the silicon loading in composite anodes to meet the increasing demands on EVs.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Yohandys A. Zulueta, My Phuong Pham-Ho, Minh Tho Nguyen
Summary: Advanced atomistic simulations were used to study ion transport in the Na- and K-doped lithium disilicate Li2Si2O5. The results showed that Na and K doping significantly enhanced Li ion diffusion and conduction in the material.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Zongying Han, Hui Dong, Yanru Yang, Hao Yu, Zhibin Yang
Summary: An efficient phase inversion-impregnation approach is developed to fabricate BaO-decorated Ni8 mol% YSZ anode-supported tubular solid oxide fuel cells (SOFCs) with anti-coking properties. BaO nanoislands are successfully introduced inside the Ni-YSZ anode, leading to higher peak power densities and improved stability in methane fuel. Density functional theory calculations suggest that the loading of BaO nanoislands facilitates carbon elimination by capturing and dissociating H2O molecules to generate OH.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Suresh Mamidi, Dan Na, Baeksang Yoon, Henu Sharma, Anil D. Pathak, Kisor Kumar Sahu, Dae Young Lee, Cheul-Ro Lee, Inseok Seo
Summary: Li-CO2 batteries, which utilize CO2 and have a high energy density, are hindered in practical applications due to slow kinetics and safety hazards. This study introduces a stable and highly conductive ceramic-based solid electrolyte and a metal-organic framework catalyst to improve the safety and performance of Li-CO2 batteries. The optimized Li-CO2 cell shows outstanding specific capacity and cycle life, and the post-cycling analysis reveals the degradation mechanism of the electrodes. First-principles calculations based on density functional theory are also performed to understand the interactions between the catalyst and the host electrode. This research demonstrates the potential of MOF cathode catalyst for stable operation in Li-CO2 batteries.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Ganghua Xiang, Zhihuan Qiu, Huilong Fei, Zhigang Liu, Shuangfeng Yin, Yuen Wu
Summary: In this study, a CeFeOx-supported Pt single atoms and subnanometric clusters catalyst was developed, which exhibits enhanced catalytic activity and stability for the preferential oxidation of CO in H2-rich stream through synergistic effect.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Dimitrios Chatzogiannakis, Marcus Fehse, Maria Angeles Cabanero, Natalia Romano, Ashley Black, Damien Saurel, M. Rosa Palacin, Montse Casas-Cabanas
Summary: By coupling electrochemical testing to operando synchrotron based X-ray absorption and powder diffraction experiments, blended positive electrodes consisting of LiMn2O4 spinel (LMO) and layered LiNi0.5Mn0.3Co0.2O2 (NMC) were studied to understand their redox mechanism. It was found that blending NMC with LMO can enhance energy density at high rates, with the blend containing 25% LMO showing the best performance. Testing with a special electrochemical setup revealed that the effective current load on each blend component can vary significantly from the nominal rate and also changes with SoC. Operando studies allowed monitoring of the oxidation state evolution and changes in crystal structure, in line with the expected behavior of individual components considering their electrochemical current loads.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Chiara Cementon, Daniel Dewar, Thrinathreddy Ramireddy, Michael Brennan, Alexey M. Glushenkov
Summary: This Perspective discusses the specific power and power density of lithium-ion capacitors, highlighting the fact that their power characteristics are often underestimated. Through analysis, it is found that lithium-ion capacitors can usually achieve power densities superior to electrochemical supercapacitors, making them excellent alternatives to supercapacitors.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Weihao Wang, Hao Yu, Li Ma, Youquan Zhang, Yuejiao Chen, Libao Chen, Guichao Kuang, Liangjun Zhou, Weifeng Wei
Summary: This study achieved an improved electrolyte with excellent low-temperature and high-voltage performance by regulating the Li+ solvation structure and highly concentrating it. The electrolyte exhibited outstanding oxidation potential and high ionic conductivity under low temperature and high voltage conditions, providing a promising approach for the practical application of high-voltage LIBs.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Martin Bures, Dan Gotz, Jiri Charvat, Milos Svoboda, Jaromir Pocedic, Juraj Kosek, Alexandr Zubov, Petr Mazur
Summary: Vanadium redox flow battery is a promising energy storage solution with long-term durability, non-flammability, and high overall efficiency. Researchers have developed a mathematical model to simulate the charge-discharge cycling of the battery, and found that hydraulic connection of electrolyte tanks is the most effective strategy to reduce capacity losses, achieving a 69% reduction.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
M. Rodriguez-Gomez, J. Campo, A. Orera, F. de La Fuente, J. Valenciano, H. Fricke, D. S. Hussey, Y. Chen, D. Yu, K. An, A. Larrea
Summary: In this study, we analysed the operando performance of industrial lead cells using neutron diffraction experiments. The experiments revealed the evolution of different phases in the positive electrode, showed significant inhomogeneity of phase distribution inside the electrode, and estimated the energy efficiency of the cells.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Jiawei Liu, Chenpeng Wang, Yue Yao, Hao Ye, Yinglong Liu, Yingli Liu, Xiaoru Xu, Zhicong Chen, Huazheng Yang, Gang Wu, Libin Lei, Chao Wang, Bo Liang
Summary: The study focuses on utilizing double conductive Ni-pads as anode collectors in micro-tubular solid oxide fuel cells. The simulation results show excellent performance and stability of DCNPs, and also highlight the potential applications in various fields.
JOURNAL OF POWER SOURCES
(2024)
Article
Chemistry, Physical
Yang Wang, Kangjie Zhou, Lang Cui, Jiabing Mei, Shengnan Li, Le Li, Wei Fan, Longsheng Zhang, Tianxi Liu
Summary: This study presents a polyimide sandwiched separator (s-PIF) for improving the cycling stability of Li-metal batteries. The s-PIF separator exhibits superior mechanical property, electrolyte adsorption/retention and ion conductivity, and enables dendrite-free Li plating/stripping process.
JOURNAL OF POWER SOURCES
(2024)
