Study on the adsorption selection of CH 4 on CuO (110) versus (111) surfaces: a density functional theory study

Abstract

Finding the active sites of suitable metal oxides is a key prerequisite for detecting CH4. The purpose of the paper is to investigate the adsorption of CH4 on intrinsic and oxygen-vacancies CuO (111) and (110) surfaces using density functional theory calculations. The results show that CH4 has a strong adsorption energy of −0.370 to 0.391 eV at all site on the CuO (110) surface. The adsorption capacity of CH4 on CuO (111) surface is weak, ranging from −0.156 to −0.325 eV. In the surface containing oxygen vacancies, the adsorption capacity of CuO surface to CH4 is significantly stronger than that of intrinsic CuO surface. The results indicate that CuO (110) has strong adsorption and charge transfer capacity for CH4, which may provide experimental guidance.