Fabrication of Z-scheme CuPd/SrTiO3–CuPd–Bi2O3 photocatalyst for converting organic dye containing N and S elements into (NH4)2SO4

ABSTRACT Several novel Z-scheme CuPd/SrTiO 3 –CuPd–Bi 2 O 3 photocatalysts are prepared via chemical reduction and calcination methods to degrade organic dyes containing N and S and convert NO 2 - , NO 3 - and SO 3 2- into (NH 4 ) 2 SO 4 . Sodium borohydride (NaBH 4 ), ascorbic acid (C 6 H 8 O 6 ) and hydrazine hydrate (N 2 H 4 ·H 2 O) are selected as reductants to deposit CuPd alloy nanoparticles on corresponding photocatalyst. The influence of solar light irradiation time on photocatalytic degradation of organic dye and conversion of the generated inorganic ions is studied. The reusability and stability of the prepared photocatalysts are assessed. The results indicate that the Z-scheme CuPd/SrTiO 3 –CuPd–Bi 2 O 3 photocatalyst prepared by using NaBH 4 has best photocatalytic activity, reusability and stability. The capture experiment of active species proves that holes play crucial roles in photocatalytic degradation of organic dyes and conversion of SO 3 2- and electrons are momentous for the conversions of NO 2 - and NO 3 - . A possible mechanism on photocatalytic degradation of organic dyes containing N and S and conversions of NO 2 - , NO 3 - and SO 3 2- into (NH 4 ) 2 SO 4 caused by Z-scheme CuPd/SrTiO 3 –CuPd–Bi 2 O 3 photocatalyst is proposed.