Zheng Lingxia, Wang Shibin, Wang Yongzhi, Zhao Zhefei, Yang Pengju, Song Jianlan, Shi Xiaowei, Zheng Huajun
Department of Applied Chemistry, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China.
State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China.
Nanotechnology. 2022 Apr 7;33(26). doi: 10.1088/1361-6528/ac5f99.
Highly efficient and inexpensive electrocatalysts for oxygen evolution reaction (OER) are extensively studied for water splitting. Herein, a unique bimetallic nanocomposite CoNi(OH)@NiCoSnanosheet arrays derived from metal-organic-frameworks (MOFs, CoNi-ZIF) is simply fabricated on Ni foam, endowing large specific surface area and outstanding electrical conductivity. Compared with their single-metallic counterparts, the bimetallic composite displays dramatically low overpotential and small Tafel slope as well as outstanding catalytic stability. The overpoptential at 20 mA cmfor CoNi(OH)@NiCoSis only 230 mV in comparison with Ni(OH)@NiS(266 mV), Co(OH)@CoS(294 mV) and RuO( = 302 mV). First-principle calculations based on density functional theory (DFT) are carried out and reveal that the introduction of Ni in Co(OH)helps lowered the energy difference of Δ-Δ, and thereby boosting the OER reactivity. This study provides an effective approach for the rational construction of low-cost metal hybrids.
用于析氧反应（OER）的高效且廉价的电催化剂在水分解研究中得到了广泛关注。在此，一种独特的双金属纳米复合材料CoNi(OH)@NiCoS纳米片阵列通过金属有机框架（MOF，CoNi-ZIF）简单地制备在泡沫镍上，赋予了其大的比表面积和出色的导电性。与单金属对应物相比，双金属复合材料表现出极低的过电位、小的塔菲尔斜率以及出色的催化稳定性。CoNi(OH)@NiCoS在20 mA cm时 的过电位仅为230 mV，相比之下，Ni(OH)@NiS为266 mV，Co(OH)@CoS为294 mV，RuO为302 mV（此处RuO后面的等号及数值不太明确原文准确意思，按原文翻译）。基于密度泛函理论（DFT）进行的第一性原理计算表明，在Co(OH)中引入Ni有助于降低Δ-Δ的能量差，从而提高OER反应活性。该研究为合理构建低成本金属杂化物提供了一种有效方法。
