Enhanced photocatalytic performance of silver-based solid solution heterojunctions prepared by hydrothermal method

Silver-based solid solution with phase heterojunctions (α/β-AgAl0.4Ga0.6O2 heterostructure) was fabricated through phase transformation under hydrothermal treatment. X-ray diffraction and Raman spectra showed the phase transformation behavior, phase structure and composition of the samples. Transmission electron microscopy illustrated the mixed morphology of near-spherical β phase together with platelet α phase and the formation of phase heterojunctions. UV-vis absorption edges of the α/β-AgAl0.4Ga0.6O2 heterostructure were adjusted from 470 to 515 nm by controlling phase ratio under different hydrothermal temperatures. The heterostructure displayed the enhanced photocatalysis activity for the degradation of methyl orange in comparison to single α or β phase. In addition, electrochemical properties including small diameter of the arc radius and maximum photocurrent indicated high separation and fast transfer efficiency of the photoinduced carriers across the phase heterojunctions. Therefore, both of the enhanced utilization of visible light and efficient carrier separation of α/β-AgAl0.4Ga0.6O2 heterostructure contributed to its excellent photocatalysis property.