With its high calorific value and low energy consumption, hydrogen is an important component of a future low-carbon energy system. Hydrogen production from electrolyzed water is the main source of obtaining hydrogen. The slow kinetics of the oxygen evolution reaction (OER) involving a four-electron reaction in the process of water electrolysis leads to the inefficiency of hydrogen production from electrolyzed water, so the development of electrocatalysts with excellent OER is of great significance. Cobalt-based catalysts are promising for electrocatalytic OER in terms of performance and cost-effectiveness, and the degree of dispersion of Co sites determines the catalytic activity. Therefore, it is of great importance to prepare highly dispersed Co-site catalysts through a convenient method. Herein, we report the facile fabrication of Co single-atom catalysts (SACs) through the use of the confined space (between the silica wall and the template) in as-prepared mesoporous silica, template-occupied KIT-6 (TOK), with abundant Si–OH. The anchoring of metal in the form of Co–O–Si was achieved by the method of grinding and calcination. CoTOK shows excellent electrocatalytic activity and cycling stability relative to the counterpart catalysts CoTFK and Co₃O₄/TFK, being promising for applications. This synthetic approach is easy to scale up, and 10 g of sample can be effortlessly synthesized using ball milling, which provides a facile method for the large-scale preparation of SACs.

中文翻译：

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密闭空间中构建钴单原子用于析氧反应

氢具有高热值、低能耗的特点，是未来低碳能源系统的重要组成部分。电解水制氢是获取氢气的主要来源。水电解过程中涉及四电子反应的析氧反应（OER）动力学缓慢，导致电解水制氢效率低下，因此开发具有优异OER的电催化剂具有重要意义。钴基催化剂在性能和成本效益方面都有望用于电催化OER，并且Co位点的分散程度决定了催化活性。因此，通过简便的方法制备高分散的Co位催化剂具有重要意义。在此，我们报告了通过使用所制备的介孔二氧化硅、模板占据的 KIT-6 (TOK) 中的有限空间（二氧化硅壁和模板之间）轻松制造 Co 单原子催化剂 (SAC)，丰富的Si-OH。通过研磨和煅烧的方法实现了 Co-O-Si 形式的金属锚固。相对于对应的催化剂CoTFK和Co ₃ O ₄ /TFK，CoTOK表现出优异的电催化活性和循环稳定性，具有广阔的应用前景。这种合成方法易于放大，使用球磨可以轻松合成10 g样品，为大规模制备SAC提供了一种简便的方法。