Preparation of Pt/γ-Bi(2)MoO(6) Photocatalysts and Their Performance in α-Alkylation Reaction under Visible Light Irradiation

Bi(NO(3))(3)·5H(2)O and (NH(4))(6)Mo(7)O(24)·4H(2)O were used as precursors to synthesize flaky γ-Bi(2)MoO(6) samples by a hydrothermal method, and Pt/γ-Bi(2)MoO(6) samples with different mass fractions were prepared by an NaBH(4) reduction method. Alpha alkylation of benzyl alcohol and acetophenone with photocatalysts under visible light irradiation was performed, and the activity of 4 wt % Pt/γ-Bi(2)MoO(6) (γ-Bi(2)MoO(6) was prepared by a nitric acid method, pH = 9, and reaction temperature 180 °C) was the best. The photocatalytic reaction conditions were optimized by changing various kinds of variables, such as the type of catalyst, solvent, and base, and the amount of base, catalyst, and reactant. The optimal conditions for the organic reaction were 75 mg 4 wt % Pt/γ-Bi(2)MoO(6), 6 mL n-heptane, 1.2 mmol NaOH, 1 mmol acetophenone, and 3 mmol benzyl alcohol. Under the optimal reaction conditions, the effects of different light wavelengths and light intensities on the reaction were measured, and the cycling ability of the photocatalyst was tested. After five cycles, the photochemical properties of the catalyst were relatively stable. Finally, the active substances were identified (such as electrons (e(−)), holes (h(+)), hydroxyl radicals (•OH), and superoxide radicals (•O(2)(−)).