Kang Hongjun, Qiao Xianshu, Jia Xin, Wang Xinzhi, Hou Guangyao, Wu Xiaohong, Qin Wei
School of Materials Science and Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, 150001, P. R. China.
School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang, 150001, P. R. China.
Small. 2024 Aug;20(32):e2309705. doi: 10.1002/smll.202309705. Epub 2024 Mar 10.
Developing high-performance electrocatalysts for oxygen evolution reaction (OER) is crucial in the pursuit of clean and sustainable hydrogen energy, yet still challenging. Herein, a spontaneous redox strategy is reported to achieve iridium single-atoms anchored on hierarchical nanosheet-based porous Fe doped β-Ni(OH) pyramid array electrodes (SAs Ir/Fe-β-Ni(OH)), which exhibits high OER performance with a low overpotential of 175 mV at 10 mA cm and a remarkable OER current density in alkaline electrolyte, surpassing Fe-β-Ni(OH)/NF and IrO by 31 and 38 times at 1.43 V versus RHE, respectively. OER catalytic mechanism demonstrates that the conversion of OH→O and the active lattice O content can be significantly improved due to the modulation effect of the Ir single atoms on the local electronic structure and the redox behavior of FeNi (oxy) hydroxide true active species. This work provides a promising insight into understanding the OER enhancement mechanism for Ir single-atoms modified FeNi-hydroxide systems.
开发用于析氧反应（OER）的高性能电催化剂对于追求清洁和可持续的氢能至关重要，但仍然具有挑战性。在此，报道了一种自发氧化还原策略，以实现锚定在分级纳米片基多孔铁掺杂β-氢氧化镍金字塔阵列电极（SAs Ir/Fe-β-Ni(OH)）上的铱单原子，该电极在10 mA cm下具有175 mV的低过电位，在碱性电解质中表现出显著的OER电流密度，在1.43 V（相对于可逆氢电极，RHE）时分别比Fe-β-Ni(OH)/NF和IrO高出31倍和38倍。OER催化机理表明，由于Ir单原子对局部电子结构的调制作用以及FeNi（氧）氢氧化物真正活性物种的氧化还原行为，OH→O的转化和活性晶格O含量可以得到显著提高。这项工作为理解Ir单原子修饰的FeNi-氢氧化物体系的OER增强机制提供了有前景的见解。
