Article
Chemistry, Physical
Jia Du, Jonathan Quinson, Alessandro Zana, Matthias Arenz
Summary: The study demonstrates that the Pt-Au nanocomposite exhibits improved ORR activity and stability compared to the benchmark, in both RDE and GDE measurements. On the other hand, the Pt-Ir nanocomposite shows better stability but lower ORR activity. By combining the GDE approach with small-angle X-ray scattering, it is shown that the improved stability of the Pt-Au nanocomposite is due to reduced Pt particle growth caused by the adjacent Au NPs.
Article
Chemistry, Physical
Ruslan M. Mensharapov, Nataliya A. Ivanova, Dmitry D. Spasov, Elena V. Kukueva, Adelina A. Zasypkina, Ekaterina A. Seregina, Sergey A. Grigoriev, Vladimir N. Fateev
Summary: Pt/C and Pt/x-SnO2/C catalysts were synthesized using a polyol method and their kinetic properties towards oxygen reduction reaction were studied by a rotating disk electrode technique in a temperature range from 1 to 50 degrees C. The addition of x-SnO2 did not reduce the catalyst activity in the temperature range of 1-30 degrees C, but a rise in temperature up to 50 degrees C resulted in a composite catalyst activity reduction of about 30%.
Article
Chemistry, Physical
Honghong Lin, Zhendong Hu, Katie H. Lim, Siwen Wang, Li Qin Zhou, Liang Wang, Gaohua Zhu, Keiichi Okubo, Chen Ling, Yu Seung Kim, Hongfei Jia
Summary: Understanding the impact of H3PO4 on catalyst activity is crucial for HT-PEMFC catalyst research. This study utilized HT-RDE to investigate the ORR in H3PO4 and found that H3PO4 reduction occurs during cyclic voltammetry, forming H3PO3. A modified protocol was developed to avoid H3PO3 generation and reliable ORR measurements were obtained. The results showed that carbon-supported PtM bimetallic alloy catalysts had higher ORR activity than Pt and that H3PO4 primarily reduces available sites for ORR.
Article
Chemistry, Physical
Sabarinathan Ravichandran, Narayanamoorthy Bhuvanendran, Qian Xu, Thandavarayan Maiyalagan, Lei Xing, Huaneng Su
Summary: The efficient oxygen bifunctional catalyst Pt-Ru-Ir with ordered mesoporous nanostructures (OMNs) and low Ir content shows promising performance in electrochemical energy conversion and storage applications, demonstrating superior activity in both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The electronic coupling between Pt, Ru, and Ir, along with the alloy formation with different lattice strain percentages, plays a significant role in enhancing the electrocatalytic performance.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Materials Science, Ceramics
Deshuang Hu, Ruyue Wang, Peng Du, Gang Li, Yonggang Wang, Dongyu Fan, Xuchao Pan
Summary: This study presents the preparation of coral-like Ru-doped cobalt oxide nanofibers by electrospinning and subsequent heat treatment, which optimizes the catalytic activity. The one-dimensional nanomaterials prepared by electrospinning exhibit a large specific surface area and rich porosity, significantly enhancing the catalytic activity.
CERAMICS INTERNATIONAL
(2022)
Article
Multidisciplinary Sciences
Yun-Fei Xia, Pan Guo, Jia-Zhan Li, Lei Zhao, Xu-Lei Sui, Yan Wang, Zhen-Bo Wang
Summary: The slow oxygen reduction reaction (ORR) has become a bottleneck for the large-scale implementation of proton exchange membrane fuel cells. There is confusion in the assessment of platinum group metals (PGMs) ORR activities, including potential conversion, test protocols, and activity calculation processes. This study demonstrates two standard calculation processes for PGM ORR activities and emphasizes the importance of using reference electrodes for accurate assessment. Additionally, the study highlights the discrepancy in ORR activities obtained via different test protocols and proposes an average adsorption model and coverage effects to explain the behavior of ORR polarization plots.
Article
Chemistry, Multidisciplinary
Ziqiang Niu, Zhankuan Lu, Zelong Qiao, Shitao Wang, Xiaohua Cao, Xiudong Chen, Jimmy Yun, Lirong Zheng, Dapeng Cao
Summary: Designing robust bifunctional catalysts for OER and HER in all-pH conditions for OWS is a promising strategy. A composite Ru-VO2 with high OWS performance is synthesized, and the synergistic effect between Ru NP and Ru-doped VO2 is revealed. This work provides new insights into the design of pH-universal catalysts for OWS.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
Chi-Yeong Ahn, Sungjun Kim, Hyuck Jae Choi, Jongmin Lee, Sun Young Kang, Ok-Hee Kim, Hyungwon Shim, Young-Shik Kim, Yung-Eun Sung, Oh Joong Kwon, Yong-Hun Cho
Summary: Research on corrosion reaction of carbon under cell reversal conditions and the effect of platinum content on fuel cell performance have been conducted, showing that catalysts with higher platinum content have better resistance to cell reversal.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Electrochemistry
Lei Xia, Fen Zhou, Hui Zhang, Zhenbin Liu, Guangfu Li, Shang Li, Mu Pan
Summary: This study investigates the instability of Pt electrode during EIS measurement in RDE. The results demonstrate that this instability is mainly reflected in the charge transfer resistance (R-ct). The range of change in R-ct strongly depends on the applied potential. During repeated EIS tests above 0.8 V, R-ct continuously increases with testing time, while the double-layer capacitance of Pt electrode decreases, indicating the formation of Pt-oxides on the electrode interface. Furthermore, stability becomes worse at higher potentials, with R-ct increasing to 3.5 times higher than the initial value after eight repeated experiments at 0.9 V.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Vera Giulimondi, Andrea Ruiz-Ferrando, Adam H. Clark, Selina K. Kaiser, Frank Krumeich, Antonio J. Martin, Nuria Lopez, Javier Perez-Ramirez
Summary: This study investigates the indirect, coordination-induced catalytic synergies in carbon-supported Ru-Pt SACs and reveals a new principle of intermetallic cooperativity.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Tsutomu Ioroi, Tsukasa Nagai, Zyun Siroma, Kazuaki Yasuda
Summary: This study investigates the parameters of the rotating disk electrode (RDE) that affect the activity evaluations for the oxygen evolution reaction (OER). Various iridium catalysts are used to examine the impacts of RDE parameters on the measured OER activity in order to obtain the activation polarization accurately. The potential range, catalyst loading, and anions in the electrolyte are found to have a significant impact on the catalytic activity. Comparison of the OER activities of the optimized RDE conditions with those determined using a labo-scale electrolyzer test cell and membrane and electrode assembly (MEA) show consistent results, indicating that the RDE half-cell with proper evaluation conditions can be a useful and rapid initial catalyst screening method to estimate the OER activity in the MEA.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Xianbin Wu, Yifan Zhang, Siyuan Chen, Xingyi Zhan, Hua Zhang, Lei Zhang, Liwei Su, Chaoqi Shen, Huan Chen, Hao Wu, Lianbang Wang
Summary: This study introduces a low-carbon CeOx/Ru@RuO2 nanosheet as an efficient cathode catalyst for Li-O2 batteries and investigates its preparation and working mechanisms using various characterization and electrochemical techniques. The nanosheet exhibits optimized Li-O reaction and Li2O2 formation, providing a new material combination and structure design for developing bifunctional catalyst materials.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Analytical
Meng-Ke Zhang, Wei Chen, Mian-Le Xu, Zhen Wei, Da Zhou, Jun Cai, Yan-Xia Chen
Summary: This study investigated the effect of buffer pairs on the pH shift at the electrode/electrolyte interface during electrochemical reactions in solutions of different bulk pHs. It established a quantitative relationship between pH(b), pH(b), pK(a), buffer pair concentration, and reaction current density, providing diagrams for estimating pH(s) and ΔpH, as well as guidelines for choosing appropriate buffer pairs to mitigate pH(s) shift induced by electrode reactions.
ANALYTICAL CHEMISTRY
(2021)
Article
Chemistry, Physical
Jia Du, Jonathan Quinson, Damin Zhang, Francesco Bizzotto, Alessandro Zana, Matthias Arenz
Summary: This study compares the electrocatalytic performance of conventional PtxIry alloy nanoparticles with Pt-IrO2 nanocomposites for bifunctional ORR/OER catalysts. Results show that the Pt-IrO2 nanocomposite concept offers advantages but also some disadvantages, especially after exposure to accelerated degradation tests. Additionally, all tested catalysts experience a decline in the Ir/Pt ratio after ADT treatment, highlighting limitations and challenges for fuel cell startup-shutdown protection and URFC stability.
Article
Chemistry, Inorganic & Nuclear
Zhiqiang Yao, Chenfeng Wang, Zengyao Wang, Guanglei Liu, Crystal Bowers, Pei Dong, Mingxin Ye, Jianfeng Shen
Summary: The development of active and cost-effective bifunctional catalysts is crucial for water dissociation through electrolysis. In this study, a bifunctional catalyst with Ni nanoparticles anchored on MoO2 nanorods was synthesized using an in situ dissolution method without using hydrogen gas. The catalyst exhibited high electrocatalytic activity and achieved extremely low overpotentials and small cell voltage for the hydrogen evolution reaction and oxygen evolution reaction. The proposed method provides a general approach for designing and fabricating transition metal oxide catalysts for water electrolysis.
DALTON TRANSACTIONS
(2022)
