Efficient Photoelectrochemical Performance of γ Irradiated g-C₃N₄ and Its g-C₃N₄@BiVO₄ Heterojunction for Solar Water Splitting

Abstract

Comprehensive experimental and density functional theory simulations have been performed for the enhanced photoelectrochemical performance of γ irradiated g-C3N4 and its heterojunction with BiVO4. The structure and morphology of g-C3N4@BiVO4 as a heterojunction were analyzed and verified from the correlation of experimental and theoretical data. It is found that γ radiations have changed the bonding structure of g-C3N4, which ultimately reduces the optical band gap energy. Moreover, the performance of γ irradiated g-C3N4 is two-fold, compared to that of the nonirradiated one, and increases from 3.59 to 5.86 μA cm–2 at 1.23 V versus Ag/AgCl in 0.5 M Na2SO4 electrolyte solution (pH 7). Finally, it is observed that the performance of γ irradiated g-C3N4 in the g-C3N4@BiVO4 heterojunction increased from 0.53 to 1.38 mA cm–2, compared to that of the nonirradiated one. In summary, it has been concluded that γ irradiated g-C3N4 and its heterojunction can potentially be applied in PEC solar water splitting.