First-principles exploration of MgTi2O5 and MgV2O5 for CO2 capture and conversion

Abstract

First-principles calculations were done to reveal the properties of MgTi2O5 and MgV2O5 for CO2 capture. The highest temperatures of MgTi2O5 and MgV2O5 for CO2 capture at different partial pressures (i.e., 0.1, 1, and 10 bar) were determined. CO2 was absorbed at higher temperatures by MgV2O5 than by MgTi2O5 at each partial pressure. Furthermore, the electronic properties of V-doped MgTi2O5 were theoretically examined to assess its potential use for photocatalytic CO2 conversion. The electronic properties of MgTi2O5 were found to be changed after V doping. Specifically, the band gap of MgTi2O5 was 2.75 eV and that of V-doped MgTi2O5 in the spin-up (down) channel was 0.48 (2.73 eV), showing the band gap decrease upon V doping.