School of Optical and Electronic Information, Huazhong University of Science and Technology , Wuhan, Hubei 430074, People's Republic of China.
ACS Appl Mater Interfaces. 2017 May 3;9(17):15176-15181. doi: 10.1021/acsami.6b14601. Epub 2017 Apr 20.
Different crystal facets with different surface atomic configurations and physical/chemical properties will have distinct electrochemical performances during their surface/near-surface redox reactions, and it is important to realize the controllable synthesis of high active surfaces for electrode materials. Herein, using first-principles calculations, the electrochemical performances of different surfaces of β-MnO were investigated. Higher surface adsorption pseudocapacitance and lower ion diffusion barrier from the surface to the near surface make the {001} surface of β-MnO superior to other surfaces when acting as an electrode material. Moreover, β-MnO with a large percentage of the {001} surface was predicted to be obtained through surface F-termination. F-termination decreases the surface energy of the {001} surface while suppressing the growth of {110} surface, which demonstrated as the surface with a much lower electrochemical performance. This work might provide a feasible strategy to synthesize anticipated surfaces with a high electrochemical performance for transition metal oxides.
不同的晶体面具有不同的表面原子构型和物理/化学性质，在其表面/近表面氧化还原反应中会表现出独特的电化学性能，因此实现对电极材料高活性表面的可控合成至关重要。本文采用第一性原理计算研究了β-MnO 的不同表面的电化学性能。从表面到近表面的更高的表面吸附赝电容和更低的离子扩散势垒使得β-MnO 的{001}表面在作为电极材料时优于其他表面。此外，通过表面 F 端基化预测可以得到具有较大比例{001}表面的β-MnO。F 端基化降低了{001}表面的表面能，同时抑制了{110}表面的生长，从而表现出电化学性能较低的表面。这项工作可能为合成具有高电化学性能的过渡金属氧化物提供了一种可行的策略。
