Barium titanate (1 0 1)/silver nanocomposite: Preparation, photocatalytic activity, and mechanism based on Density Functional Theory

In this study, the tetragonal phase barium titanate (T-BT) with (1 0 1) facet could be prepared by a simple rotary evaporation precursor system at 800 ℃ for 2 h. (1 0 1) T-BT was modified by photodeposition, and then Ag nanoparticles with diameter of 10–20 nm were grown on the surface of (1 0 1) T-BT to obtain T-BT/Ag. The samples were analyzed by XRD, SEM, XPS and TEM. The photocatalytic performance of T-BT and T-BT/Ag was measured by degradation of MO (Methyl Orange) and RhB (Rhodamine B). T-BT could degrade 1.95 % of MO or 1.09 % of RhB under the parameter of 0.01 mol/L-2 min within 120 min. However, under the same conditions, T-BT/Ag composite powder had the best degradation efficiency, which could degrade 86.7 % of MO or 63.8 % of RhB respectively. The photoluminescence spectrum, electrochemical impedance spectrum, ultraviolet visible diffuse reflectance spectroscopy analysis and Density Functional Theory (DFT) calculation results showed that the O on the surface of (1 0 1) crystal facet of T-BT could bond with (1 1 1) Ag and reached the most stable state.++++.