A New Application of Nanocrystal In2S3 in Efficient Degradation of Organic Pollutants under Visible Light Irradiation

The nanocrystal In 2 S 3 (nc-In 2 S 3 ) has been used as a visible light active photocatalyst. The optical absorption indicated a narrow band gap ( E g =1.9 eV) for nc-In 2 S 3 . Compared with TiO 2− x N x, the decomposition of methyl orange using nc-In 2 S 3 revealed enormously enhanced visible light activity. The ·OH during the photocatalytic degradation process was detected by terephthalic acid photoluminescence probing technique (TA-PL). The organic intermediate products were successfully separated by liquid chromatogram and subsequently identified by an electrospray ionization (ESI) mass spectral technique. The possible photocatalytic mechanism is presented.