Study on the controlled synthesis and photocatalytic performance of rare earth Nd deposited on mesoporous TiO2 photocatalysts

Abstract

Nanosized TiO2 photocatalysis technology is one of the most promising technologies for the treatment of wastewater containing azo dyes. In this work, TiO2 was deposited on a mesoporous SBA-15 molecular sieve by chemical deposition, and rare earth (RE) metal neodymium (Nd) was further deposited on the surface of the catalyst to obtain an Nd–TiO2–SBA-15 photocatalyst. The prepared photocatalyst was analyzed by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDS), and N2 adsorption–desorption. The activity of the Nd–TiO2–SBA-15 photocatalyst was evaluated by using methyl orange to represent the azo dye. The effects of different Nd deposition amounts and different solution pH values on the photocatalyst performance were principally studied. The results show that the synthesized photocatalyst formed an anatase crystal with a mesoporous structure. The specific surface area and pore size of the photocatalyst are 548.2 m2/g and 6.5 nm, respectively. As the amount of Nd deposition gradually increases, the activity of photocatalyst undergoes a process of first rising and then decreasing. In addition, the photocatalyst maintains high photocatalytic activity in the pH range of 2–10, exhibiting good acid–base adaptability. This work demonstrates that the Nd–TiO2–SBA–15 nanophotocatalyst has broad practical application prospects on a large scale.