Journal of the American Chemical Society
·
2021
·
IF 15.419
Yaming Hao,Yefei Li,Jianxiang Wu,Lingshen Meng,Jinling Wang,Chenglin Jia,Tao Liu,Xuejing Yang,Zhi-Pan Liu,Ming Gong
NiFe oxyhydroxide is one of the most promising oxygen evolution reaction (OER) catalysts for renewable hydrogen production, and deciphering the identity and reactivity of the oxygen intermediates on its surface is a key challenge but is critical to the catalyst design for improving the energy efficiency. Here, we screened and utilized in situ reactive probes that can selectively target specific oxygen intermediates with high rates to investigate the OER intermediates and pathway on NiFe oxyhydroxide. Most importantly, the oxygen atom transfer (OAT) probes (e.g., 4-(diphenylphosphino) benzoic acid) could efficiently inhibit the OER kinetics by scavenging the OER intermediates, exhibiting lower OER currents, larger Tafel slopes, and larger kinetic isotope effect (KIE) values, while probes with other reactivities demonstrated much smaller effects. Combining the OAT reactivity with electrochemical kinetic and operando Raman spectroscopic techniques, we identified a resting Fe═O intermediate in the Ni–O scaffold and a rate-limiting O–O chemical coupling step between a Fe═O moiety and a vicinal bridging O. DFT calculation further revealed a longer Fe═O bond formed on the surface and a large kinetic energy barrier of the O–O chemical coupling step, corroborating the experimental results. These results point to a new direction of liberating lattice O and expediting O–O coupling for optimizing NiFe-based OER electrocatalyst.
研究领域:
电化学
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催化科学
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材料科学
✓ 已验证
DOI
PubMed
高影响因子
ACS Catalysis
·
2024
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IF 11.3
Minghui Cui,Rongjing Guo,Yansong Zhou,Wenqi Zhao,Yanjing Liu,Wenbo Luo,Qiongrong Ou,Shuyu Zhang
The efficiency of hydrogen production from water electrolysis is mainly restricted by the sluggish oxygen evolution reaction (OER). The mainstream adsorbate evolution mechanism and lattice oxygen-mediated mechanism face a trade-off between performance and stability, while the diatomic oxygen mechanism (DOM) based on the O–O coupling provides a solution to overcome this limitation. However, the intrinsic principles that facilitate the O–O coupling remain unclear, which complicates material design. In this work, we use spinel Co3O4 as a model and identify that the asymmetric sites formed by the octahedral Co with O defects and the original octahedral Co are effective sites for O–O coupling. Based on this, we propose using the degree of asymmetry of the dual site as a descriptor to quantify the reaction free energy of rate-determining step along the DOM pathway, presenting a volcano plot relationship. Experimental validation shows that plasma-prepared Co3O4 enables O–O coupling, requiring only 287 and 420 mV overpotentials to achieve current densities of 10 and 1000 mA cm–2 in 0.5 M H2SO4, respectively. This work demonstrates efficient sites for the OER along the DOM pathway in Co3O4, providing valuable insights for designing high-performance OER catalysts.
研究领域:
材料科学
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电催化
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2023
·
IF 17.1
Chen Qiao,Zahid Usman,Jie Wei,Lin Gan,Jianhua Hou,Yingying Hao,Youqi Zhu,Jiatao Zhang,Chuanbao Cao
A catalyst kinetics optimization strategy based on tuning active site intermediates adsorption is proposed. Construction of the M-OOH on the catalytic site before the rate-determining step (RDS) is considered a central issue in the strategy, which can optimize the overall catalytic kinetics by avoiding competition from other reaction intermediates on the active site. Herein, the kinetic energy barrier of the O–O coupling for as-prepared sulfated Co-NiFe-LDH nanosheets is significantly reduced, resulting in the formation of M-OOH on the active site at low overpotential, which is directly confirmed by in situ Raman and charge transfer fitting results. Moreover, catalysts constructed from active sites of highly efficient intermediates make a reliable model for studying the mechanism of the OER in proton transfer restriction. In weakly alkaline environments, a sequential proton–electron transfer (SPET) mechanism replaces the concerted proton–electron transfer (CPET) mechanism, and the proton transfer step becomes the RDS; high-speed consumption of reaction intermediates (M-OOH) induces sulfated Co-NiFe-LDH to exhibit excellent kinetics.
研究领域:
催化化学
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材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-11
·
IF 15.7
He Chun-Ting,Yu Li-Hong,Liu Haiming,Wang Qing,Ye Zi-Ming,Zhang Jia,Wang Li-Dong,He Mei-Qian,Zhang Xue-Feng,Du Hong-Gang,Lu Zi-Wei,Yang Jian,Huang Hai-Hua,Chen Xiao-Ming
Covalently bonded metal-free electrocatalysts exhibit significant potential for sustainable energy technologies, yet their performances remain unsatisfactory compared with metal-based catalysts. Herein, we propose an all-organic electrocatalyst, MEC-2, that conforms to the infrequent oxide path mechanism in alkaline oxygen evolution reaction through post-oxidation modification. MEC-2 achieves an intrinsic overpotential of 257.7 ± 0.6 mV at 10 mA·cm −2 and possesses durability with negligible degradation over 100,000 CV cycles or 250 h of operation at 1.0 A·cm −2 , being comparable to the advanced metal-based OER electrocatalysts. The 18 O-labeled operando characterization and theoretical calculations unveil that post-oxidation modification enhances the electron affinity to OH intermediates, and adjusts the adsorption configuration and proximity distance of O intermediates, thereby promoting direct O−O radical coupling. In this work, we show a fresh perspective for understanding the role of non-metallic elements/functional groups in electrocatalysis, and to a certain extent, narrows the gap between all-organic electrocatalysts and metal-based electrocatalysts.
研究领域:
能源材料科学
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电化学
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理论计算
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Moxing Cheng,Haoyun Sheng,Yin’an Zhu,Ziqi Tian,Yichao Lin
The development of highly active and durable catalysts for the acidic oxygen evolution reaction (OER) is urgently needed to accelerate reaction kinetics and reduce energy barriers. Herein, we propose to tune the local electronic structure in RuO 2 via yttrium ion (Y 3+ ) doping to facilitate the OER process following oxide path mechanism (OPM). The electron-deficient of Y 3+ redistributes local charge density, strengthens metal–oxygen bonds to suppress lattice degradation. Moreover, the incorporation of larger Y 3+ radius reduce the Ru–Ru distance, and thereby benefits O–O coupling. The optimized Y 0.11 Ru 0.89 O 2−δ catalyst exhibits an exceptionally low overpotential of 195 mV at 10 mA cm −2 for acidic OER and operates stably for 250 h at 100 mA cm −2 in a PEM electrolyzer. Theoretical investigations reveal that Y–O–Ru structure effectively modifies the chemical environment and optimizes the atomic configuration of active sites. This study establishes electron-deficient, large-radius dopants as an effective strategy for designing efficient and durable acidic OER catalysts, enhancing RuO 2 performance.
研究领域:
电催化
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材料化学
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能源科学
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表面科学
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无机化学
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电化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）