The Flexibility of an Amorphous Cobalt Hydroxide Nanomaterial Promotes the Electrocatalysis of Oxygen Evolution Reaction
The Flexibility of an Amorphous Cobalt Hydroxide Nanomaterial Promotes the Electrocatalysis of Oxygen Evolution Reaction
复制标题
非晶态氢氧化钴纳米材料的柔性促进析氧反应的电催化
DOI：
10.1002/smll.201703514
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发表时间：
2018-04-26
期刊：
影响因子：
13.3
通讯作者：
Guo, Lin
中科院分区：
文献类型：
--
作者：
Liu, Juzhe;Nai, Jianwei;Guo, Lin
结构灵活性可以是操作催化剂的期望特性，因为它使自身适应于给定的催化过程以提高活性。结果表明，非晶态氢氧化钴纳米笼是一种很有前途的电催化剂，在电催化析氧反应条件下，其过电位在10 mA cm（-2）时为0.28 V，远远优于晶态氢氧化钴纳米笼，在同类催化剂中处于前列。从原位和非原位的直接实验结果来看，这种增强的活性归因于其在以下方面的高结构灵活性：1）容易和整体转化为催化活性相; 2）容纳氧空位;以及3）实时过程中的结构自调节。值得注意的是，基于合理的催化机制和计算模拟结果，公开了这种结构灵活性如何促进析氧反应的动力学。这项工作加深了对钴基催化剂在电化学催化中的结构-活性关系的理解，并激发了更多需要这种无定形纳米材料实现的柔性结构的应用。
Structural flexibility can be a desirable trait of an operating catalyst because it adapts itself to a given catalytic process for enhanced activity. Here, amorphous cobalt hydroxide nanocages are demonstrated to be a promising electrocatalyst with an overpotential of 0.28 V at 10 mA cm(-2), far outperforming the crystalline counterparts and being in the top rank of the catalysts of their kind, under the condition of electrocatalytic oxygen evolution reaction. From the direct experimental in situ and ex situ results, this enhanced activity is attributed to its high structural flexibility in terms of 1) facile and holistic transformation into catalytic active phase; 2) hosting oxygen vacancies; and 3) structure self-regulation in a real-time process. Significantly, based on plausible catalytic mechanism and computational simulation results, it is disclosed how this structural flexibility facilitates the kinetics of oxygen evolution reaction. This work deepens the understanding of the structure-activity relationship of the Co-based catalysts in electrochemical catalysis, and it inspires more applications that require flexible structures enabled by such amorphous nanomaterials.