Celastrol-modified TiO2 nanoparticles: effects of celastrol on the particle size and visible-light photocatalytic activity

Abstract

In this study, celastrol (CSL), a triterpene compound which is derived from the Chinese medicinal plant Tripterygium wilfordii, was used to synthesize CSL-modified TiO₂ nanoparticles by a hydrothermal treatment method. The nanoparticles phase, morphology, surface structures, as well as the visible-light photocatalytic activities were studied. The modification of CSL does not alter the crystalline structure of the TiO₂ but can prevent TiO₂ from further aggregating and provides photosynthesis pigments as an in situ dye-sensitizing source. Compared to pure TiO₂, the resulting CSL-modified TiO₂ nanoparticles exhibit enhanced visible-light photocatalytic activity and showed an excellent cyclic stability in the decomposition of methylene blue (MB). In addition, the photocatalytic degradations of MB were all demonstrated to follow a first-order kinetic model. The enlarged specific surface area and CSL-modified surface improved the visible-light photocatalytic activity of nanoparticles.