PdO loaded WO3 composite with Na2W4O13 flake: A 2-D heterostructure composite material

In this study, a heterostructure was prepared by two dimensional Na2W4O13 flake and mixture of 0 dimensional WO3 and PdO. Following that, the structure was characterized. TEM (transmission electron microscopy) results showed that the WO3 particle loaded with PdO and decorated on surface of the two-dimensional Na2W4O13 flake. Compared with WO3 and Na2W4O13, the as-prepared 2-D composite showed an additional absorption band in the visible range (400-800 nm), which conduced to an improvement of the overall photonharvesting efficiency. At 0.5% mole ratio PdO loaded, the synthesized composite shows the highest photocatalytic disinfection activity under visible illumination, exceeding about four times than that of pure WO3 and five times than that of pure Na2W4O13, respectively. By detecting PL spectroscopy (photoluminescence spectroscopy), the intensities of emission from 0.5% PdO loaded WO3/Na2W4O13 composite were found to be weaker than those from other materials, which explained the higher disinfection activity of this composite.