Enhanced Photocatalytic Activity of 2H-MoSe2 by 3d Transition-Metal Doping

To develop MoSe2-based photocatalysts, increasing the catalytic activity of 2H-MoSe2 is essential. In this work, the electronic and photocatalytic properties of 3d transition metal-doped (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn) 2H-MoSe2 were investigated by first-principles calculations. The results indicate that Sc, Ti, V, Cr, Mn, Fe, and Co atoms tend to substitute the Mo atoms under a Se-rich condition, whereas Ni, Cu, and Zn atoms prefer to occupy the interstitial positions. More importantly, Sc- and Ti-doped 2H-MoSe2 can enhance the photocatalytic activity by increasing the oxidizability of photogenerated holes, suppressing the recombination of photogenerated carriers, and increasing the number of catalytic active sites.