Barium titanate (101)/silver nanocomposite: Preparation, photocatalytic activity, and mechanism based on Density Functional Theory

[Display omitted] •Ag nanoparticles with diameter of 10–20 nm were grown on the surface of tetragonal BaTiO3 to obtain composites.•The tetragonal BaTiO3/Ag composite powder obtained under the parameter of 0.01 mol/L-2 min has the best degradation efficiency.•The tetragonal BaTiO3/Ag composite powder is an effective photocatalyst, which can degrade 86.7 % MO or 63.8 % of RHB within 120 min.•Density functional theory calculation showed that the O on the surface of (101) crystal facet of tetragonal BaTiO3 could bond with (111) Ag and reached the most stable state. In this study, the tetragonal phase barium titanate (T-BT) with (101) facet could be prepared by a simple rotary evaporation precursor system at 800 ℃ for 2 h. (101) T-BT was modified by photodeposition, and then Ag nanoparticles with diameter of 10–20 nm were grown on the surface of (101) 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 (101) crystal facet of T-BT could bond with (111) Ag and reached the most stable state.+++.