A periodic DFT study of ammonia adsorption on the V2O5 (001), V2O5 (010) and V2O5 (100) surfaces: Lewis versus Brönsted acid sites

► On the basal V2O5 (001), NH3 adsorbs preferentially at Brönsted acid sites. ► On side (010) and (100), NH3 adsorbs strongly at Brönsted and Lewis acid sites. ► Surface relaxations have no influence on NH3 adsorption on saturated (001) surface. ► NH3-adsorption energies on (010) and (100) surfaces depend on the relaxed models.