A First-principles Study on the Gas Sensitivity of Metal-loaded Graphene with an Atomic Vacancy to O2

摘要

In this work,adsorption energies,geometrical and electronic structures for adsorption systems of O2 at metal-loaded graphene (M-Gra) and metal-loaded defective graphene (M-D-Gra) (M =Ni,Pd,Pt and Al) surfaces are studied using a GGA-PW91 method.Calculated results show that loaded M make the interaction between O2 and the graphene surface change from physical to chemical adsorptions,band gaps of M-Gra systems after the O2 adsorption change,and the Ni-loaded Gra has the highest sensitivity to O2.For O2-M-D-Gra systems,interactions between O2 and the M-D-Gra surfaces are chemical,similar to the O2-M-Gra systems,and loaded Pt and Al have the strongest effect on the sensitivity of D-Gra to O2.The M loads at the perfect Gra and D-Gra surfaces make the interactions between O2 and the surfaces have obvious charge transfer.This work would provide a valuable guidance on the gas sensitivity study of graphene to O2.