A first principles study of gas adsorption on charged CuBTC

► Charge variation of the open Cu in CuBTC influences the gas adsorption behaviors. ► The binding strengths of CO, O2 and N2 are enhanced in negatively-charged CuBTC. ► Their binding nature exhibits chemisorptive. ► Positively-charged CuBTC slightly improves the adsorption strength of CO2.