TY - JOUR
T1 - Facet-Dependent Surface Restructuring on Nickel (Oxy)hydroxides
T2 - A Self-Activation Process for Enhanced Oxygen Evolution Reaction
AU - Yao, Yunduo
AU - Zhao, Guangming
AU - Guo, Xuyun
AU - Xiong, Pei
AU - Xu, Zhihang
AU - Zhang, Longhai
AU - Chen, Changsheng
AU - Xu, Chao
AU - Wu, Tai Sing
AU - Soo, Yun Liang
AU - Cui, Zhiming
AU - Li, Molly Meng Jung
AU - Zhu, Ye
N1 - Publisher Copyright:
© 2024 American Chemical Society.
PY - 2024/6/5
Y1 - 2024/6/5
N2 - Unraveling the catalyst surface structure and behavior during reactions is essential for both mechanistic understanding and performance optimization. Here we report a phenomenon of facet-dependent surface restructuring intrinsic to β-Ni(OH)2 catalysts during oxygen evolution reaction (OER), discovered by the correlative ex situ and operando characterization. The ex situ study after OER reveals β-Ni(OH)2 restructuring at the edge facets to form nanoporous Ni1-xO, which is Ni deficient containing Ni3+ species. Operando liquid transmission electron microscopy (TEM) and Raman spectroscopy further identify the active role of the intermediate β-NiOOH phase in both the OER catalysis and Ni1-xO formation, pinpointing the complete surface restructuring pathway. Such surface restructuring is shown to effectively increase the exposed active sites, accelerate Ni oxidation kinetics, and optimize *OH intermediate bonding energy toward fast OER kinetics, which leads to an extraordinary activity enhancement of ∼16-fold. Facilitated by such a self-activation process, the specially prepared β-Ni(OH)2 with larger edge facets exhibits a 470-fold current enhancement than that of the benchmark IrO2, demonstrating a promising way to optimize metal-(oxy)hydroxide-based catalysts.
AB - Unraveling the catalyst surface structure and behavior during reactions is essential for both mechanistic understanding and performance optimization. Here we report a phenomenon of facet-dependent surface restructuring intrinsic to β-Ni(OH)2 catalysts during oxygen evolution reaction (OER), discovered by the correlative ex situ and operando characterization. The ex situ study after OER reveals β-Ni(OH)2 restructuring at the edge facets to form nanoporous Ni1-xO, which is Ni deficient containing Ni3+ species. Operando liquid transmission electron microscopy (TEM) and Raman spectroscopy further identify the active role of the intermediate β-NiOOH phase in both the OER catalysis and Ni1-xO formation, pinpointing the complete surface restructuring pathway. Such surface restructuring is shown to effectively increase the exposed active sites, accelerate Ni oxidation kinetics, and optimize *OH intermediate bonding energy toward fast OER kinetics, which leads to an extraordinary activity enhancement of ∼16-fold. Facilitated by such a self-activation process, the specially prepared β-Ni(OH)2 with larger edge facets exhibits a 470-fold current enhancement than that of the benchmark IrO2, demonstrating a promising way to optimize metal-(oxy)hydroxide-based catalysts.
UR - http://www.scopus.com/inward/record.url?scp=85194169977&partnerID=8YFLogxK
U2 - 10.1021/jacs.4c02292
DO - 10.1021/jacs.4c02292
M3 - Journal article
C2 - 38775440
AN - SCOPUS:85194169977
SN - 0002-7863
VL - 146
SP - 15219
EP - 15229
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 22
ER -