Facile synthesis of BaMoO4 and BaMoO4/BaWO4 heterostructures with type-I band arrangement and enhanced photoluminescence properties

A series of BaMoO4 and BaMoO4/BaWO4 phosphors were successfully prepared via a polyacrylamide gel method and low temperature calcination technology. The effects of sintering temperature and mass percentage of BaMoO4/BaWO4 on the phase purity, functional group, surface morphology, charge state, photoluminescence properties and photocatalytic activity of the prepared products were studied in detail. The results indicate that the BaMoO4 phosphor is a scheelite tetragonal structure with high crystallinity. The photoluminescence spectra indicates that the phosphors have a strong blue emission peak at 440 nm with excitation wavelength of 282 nm for the BaMoO4 phosphor, and three emission peaks at 400, 440 and 460 nm with excitation wavelength of 284 nm for the BaMoO4/BaWO4 phosphors. These photoluminescence behaviors can be ascribed to the T-1(2)->(1)A(1) transition, Jahn-Teller distorted tetrahedral symmetry of [MoO4](2-) and surface defect. Photocatalytic experiments further confirmed that the BaMoO4/BaWO4 phosphors exhibit a high recombination rate of electron hole pairs. The result further indicates that the type-I band arrangement structure of BaMoO4/BaWO4 phosphors is beneficial to enhance the photoluminescent properties of single-phase phosphors. This study provides a novel route for preparing the type-I band arrangement structure composite phosphors with high photoluminescent properties and potential applications in light emitting devices, optoelectronic devices, laser devices and white pigments. (C) 2021 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.