Ruthenium Complex of sp<sup>2</sup> Carbon‐Conjugated Covalent Organic Frameworks as an Efficient Electrocatalyst for Hydrogen Evolution
Yuxiang Zhao, Ying Liang, Daoxiong Wu, Hao Tian, Tian Xia, Wenxin Wang, Weiyu Xie, Xin‐Ming Hu, Xinlong Tian, Qi Chen
Abstract
Abstract It is still a great challenge to explore hydrogen evolution reaction (HER) electrocatalysts with both lower overpotential and higher stability in acidic electrolytes. In this work, an efficient HER catalyst, Ru@COF‐1, is prepared by complexation of triazine‐cored sp 2 carbon‐conjugated covalent organic frameworks (COFs) with ruthenium ion. Ru@COF‐1 possesses high crystallinity and porosity, which are beneficial for electrocatalysis. The large specific surface area and regular porous channels of Ru@COF‐1 facilitate full contact between reactants and catalytic sites. The nitrogen atoms of triazines are protonated in the acidic media, which greatly improve the conductivity of Ru@COF‐1. This synergistic effect makes the overpotential of Ru@COF‐1 about 200 mV at 10 mA cm –2 , which is lower than other reported COFs‐based electrocatalysts. Moreover, Ru@COF‐1 exhibits exceptionally electrocatalytic durability in the acidic electrolytes. It is particularly stable and remains highly active after 1000 cyclic voltammetry cycles. Density functional theory calculations demonstrate that tetracoordinated Ru‐N 2 Cl 2 moieties are the major contributors to the outstanding HER performance. This work provides a new idea for developing protonated HER electrocatalysts in acidic media.