摘要
La/WO 3 system were successfully built via a simply crystallization precipitation method using sodium tungstate and lanthanum nitrate hexahydrate as precursor. Samples were characterized by powder X-ray diffraction, UV–Vis absorbance spectroscopy, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, and N 2 adsorption–desorption isotherms (BET). Results showed that La does not enter into the crystal lattice of WO 3 but located in the interstitial site and accordingly presented as the form of La–O–W in the interstitial site. In addition, doping of La restrict the grain size and the minimum crystal size was 28 nm at La:W = 3:10. Photocatalytic degradation of Rhodamine B showed that the modified samples had better catalytic performance. When La:W reaches 0.3, the La/WO 3 nano-materials exhibits the highest photocatalytic activity, which can be attributed to the synergic effect of the higher BET surface area, surface hydroxyl content and optimum La contents. A possible mechanism for the photocatalytic degradation of RhB has also been provided.
危险品化学品经营许可证(带存储)