Ni-MoTiNO用于电化学N_(2)还原反应的理论研究  

Theoretical Study of Ni-MoTiNO for Electrochemical N_(2)Reduction Reaction

作　　者：曹琦 崔璐瑶 CAO Qi;CUI Luyao(College of Chemistry and Chemical Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学化学与化工学院,太原030024

出　　处：《人工晶体学报》2025年第4期708-716,共9页Journal of Synthetic Crystals

基　　金：国家自然科学基金(21978187);山西省自然科学基金(202203021221058)。

摘　　要：电化学氮气还原反应(ENRR)是替代Haber-Bosch工艺合成氨的可持续发展技术之一,其核心问题是寻找高催化活性和高选择性的稳定电催化剂。过渡金属氮氧化物(TMNO)表面遵循Mars-van Krevelen(MvK)机理路径进行合成氨反应,表现出比传统缔合机理更有利的N_(2)吸附和活化,其设计双位点活性催化剂成为高效催化研究的热点。本文选用具有最佳ENRR表现的双位点MoTiNO作为基底,通过密度泛函理论(DFT)计算方法负载Ni构建了Ni-MoTiNO结构作为电化学N_(2)还原催化剂,进行了结构稳定性、双位点吸附行为、基于原子氢(^(*)H)迁移辅助MvK机理的ENRR催化活性和电子性质分析四方面的研究。计算结果表明,Ni-MoTiNO表面的双位点(Ni和Nv)协同作用既促进了^(*)H迁移,又有效打破了ENRR中*N相关中间体吸附能力和产物脱附能力的线性比例关系。实验证明,合成的Ni-MoTiNO能够有效实现NH 3合成并具有较高的选择性。The electrochemical nitrogen reduction reaction(ENRR)is one of the sustainable development technologies for the synthesis of NH 3 to replace the Haber-Bosch process.The core issue is to find stable electrocatalysts with high catalytic activity and selectivity.Since the transition metal oxynitrides(TMNO)surface follows the Mars-van Krevelen(MvK)mechanism pathway for ammonia synthesis reaction,it exhibits more favorable N_(2)adsorption and activation than the conventional association mechanism.Based on this,Ni was selected to be loaded on dual-sites MoTiNO with the best ENRR performance,and the Ni-MoTiNO structure was constructed as an electrochemical N_(2)reduction catalyst by the density function theory(DFT)calculation method,and four aspects,including the structural stability,two-site adsorption behaviors,ENRR catalytic activity based on the^(*)H-migration-assisted MvK mechanism,and the analysis of the electronic properties,were investigated.Results show that the synergistic action of the dual sites(Ni and Nv)on the surface of Ni-MoTiNO both promotes^(*)H migration and effectively breaks the linear proportionality between the strong adsorption of*N-related intermediates and the difficulty in resolving the products in ENRR.Experiments have proved that the synthesized Ni-MoTiNO can effectively achieve ammonia synthesis and has a relatively high selectivity.

关 键 词：合成氨 MvK机理 电催化 氮空位 MoTiNO 负载 

分 类 号：O643.3[理学—物理化学]