Photocatalytic Conversion of CO 2 by H 2 O as an Electron Donor over NaTaO 3 with Controlled Morphologies Using a Series of Cocatalysts

Abstract The morphology of the primary semiconductor material is an essential factor for the performance of photocatalysts. In this work, we synthesized the cubic facet (100) and the anisotropic facets ((100) and (110)) of NaTaO 3 as photocatalysts. They were assessed by the photocatalytic conversion of CO 2 using H 2 O as the electron donor and a series of cocatalysts, including Ga(OH) 3 , Cd(OH) 2 , Zn(OH) 2 , and amorphous ZnGa 2 O 4 , relative to Ag nanoparticles as a conventional cocatalyst. The results demonstrated that the performances of studied cocatalysts depended on the morphologies of NaTaO 3 . Ga(OH) 3 (3.0 vs. 20.1 μmol h −1 ), Zn(OH) 2 (23.1 vs. 52.4 μmol h −1 ), amorphous ZnGa 2 O 4 (37.4 vs. 85.5 μmol h −1 ), and Ag nanoparticles (48.9 vs. 92.4 μmol h −1 ) exhibited higher formation rates of CO over anisotropic NaTaO 3 than the cubic ones. On the contrary, Cd(OH) 2 (62.1 vs. 32.3 μmol h −1 ) cocatalyst exhibited higher performance over cubic NaTaO 3 than the anisotropic ones.