电化学2017，Vol.23Issue(4)：369-380,12.DOI:10.13208/j.electrochem.170141
基于一氧化碳、二氧化碳和氧气分子吸附为探针的碳化钼、碳化钨、氮化钼和氮化钨的表面化学性质:密度泛函理论分析
Surface Chemical Properties of Mo2C, W2C, Mo2N and W2N Probed with CO, CO2 and O2 Adsorption: A DFT Analysis
摘要
Abstract
Transition metal carbides and nitrides are attractive materials for electrodes in many electrochemical energy storage and conversion applications.In the present study,we use density functional theory slab calculations to characterize the surface chemical properties of molybdenum (Mo) and tungsten (W) carbides and nitrides,namely,Mo2C,W2C,Mo2N and W2N with the adsorption of CO,CO2 and O2.These probing molecules provide measures in both acidity/basicity and redox property for the surfaces of these carbides and nitrides.Our results show that Lewis basic sites were responsible for CO2 adsorption and the basicity followed an order of α-W2C(001) ＞ α-W2N(001) ＞ β-Mo2C(001) ＞ γ-Mo2N(100).Both CO and O2 adsorption provide measures in the reducing ability of these carbides and nitrides.The results showed a reducing ability in the order of β-W2C(100) ＞ α-Mo2C(100) ＞ α-W2N(001) ＞ o-W2C(001) ＞ β-Mo2C(001) ＞ γ-Mo2N(100).The reducing nature of these carbides and nitrides make them good candidates to substitute noble metals in various catalytic reactions.关键词
密度泛函理论/过渡金属碳化物/过渡金属氮化物/氧化还原位/酸性/碱性Key words
density functional theory/transition metal carbides/transition metal nitrides/redox sites/acidity/basicity分类
化学化工引用本文复制引用
叶静云,张天雨,徐凌云,殷淑霞,Krishanthi Weerasinghe,Pamela Ubaldo,和平,葛庆峰..基于一氧化碳、二氧化碳和氧气分子吸附为探针的碳化钼、碳化钨、氮化钼和氮化钨的表面化学性质:密度泛函理论分析[J].电化学,2017,23(4):369-380,12.基金项目
We acknowledge the support of NSF-CBET program (Award No.CBET-1438440). （Award No.CBET-1438440）
