CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100190, China.
School of Science, North University of China, Taiyuan 030051, China.
J Colloid Interface Sci. 2019 Jan 1;533:503-512. doi: 10.1016/j.jcis.2018.08.104. Epub 2018 Aug 29.
The electrochemical oxygen evolution reaction (OER) is sparked extensive interest in efficient energy storage and conversion. Cobalt Selenide (CoSe) is believed to be one of the promising candidates for OER based on Yang Shao-Horn's principle. However, owing to low exposure of active sites and/or low efficiency of electron transfer, the electrocatalytic activity of CoSe is far less than expected. In this work, a novel carbon nanotubes (CNT) grafted 3D core-shell structured CoSe@C-CNT nanohybrid is developed by a general hydrothermal-calcination strategy. Zeolite imidazole frameworks (ZIF) was used as the precursor to synthesis of the materials. It is found that both the calcination temperature and the selenium content can significantly regulate the catalytic performance of the hybrids. The obtained best catalysts requires the overpotential of only 306 mV and 345 mV to reach a current density of 10 mA cm and 50 mA cm in 1.0 MKOH medium, respectively. It also exhibits a small Tafel slope of 46 mV dec and excellent durability, which is superior to most of recently reported CoSe-based and Co-based materials. These superior performances can be ascribed to synergistic effects of the highly active CoSe nanostructure, defect carbon species and the carbon nanotubes exist in the catalyst. Besides, the unique morphology leads to large electrochemical surface area of the catalyst, which is in favor of the exposure of active sites for OER. Due to high efficiency, low cost and excellent durability for OER, the prepared catalysts showed can be potentially used to substitute noble metals utilized in related energy storage and conversion devices.
电化学氧气析出反应（OER）在高效储能和转化方面引起了广泛的兴趣。根据杨绍鸿的原理，硒化钴（CoSe）被认为是 OER 的有前途的候选材料之一。然而，由于活性位点的暴露不足和/或电子转移效率低，CoSe 的电催化活性远低于预期。在这项工作中，通过一种通用的水热-煅烧策略，开发了一种新型的碳纳米管（CNT）接枝的 3D 核壳结构 CoSe@C-CNT 纳米杂化物。沸石咪唑酯骨架（ZIF）被用作合成材料的前体。研究发现，煅烧温度和硒含量都可以显著调节杂化物的催化性能。获得的最佳催化剂在 1.0MKOH 介质中仅需要 306mV 和 345mV 的过电势即可达到 10mA/cm 和 50mA/cm 的电流密度。它还表现出 46mV/dec 的小塔菲尔斜率和出色的耐久性，优于大多数最近报道的基于 CoSe 和 Co 的材料。这些优异的性能可以归因于高度活性的 CoSe 纳米结构、缺陷碳物种和催化剂中存在的碳纳米管之间的协同效应。此外，独特的形态导致催化剂的电化学表面积较大，有利于 OER 活性位点的暴露。由于 OER 具有高效率、低成本和出色的耐久性，所制备的催化剂有望替代相关储能和转换设备中使用的贵金属。
