Synthesis of In2S3–CNT nanocomposites for selective reduction under visible light

Abstract

In₂S₃–carbon nanotube (In₂S₃–CNT) nanocomposites have been prepared via a facile refluxing wet chemistry process. The as-synthesized In₂S₃–CNT nanocomposites can be used as selective and active visible-light-driven photocatalysts toward hydrogenation of nitroaromatics to amines in water. Photoirradiation (λ > 420 nm) of In₂S₃–CNT photocatalysts suspended in water containing nitroaromatics produces the corresponding amines with high yields. The control experiments reveal that an inert atmosphere and the addition of a hole scavenger are both indispensable for the visible-light-driven photocatalytic hydrogenation of nitroaromatics over In₂S₃–CNT. In comparison with blank In₂S₃, the obviously enhanced photocatalytic performance of the In₂S₃–CNT photocatalyst is mainly ascribed to the unique physicochemical properties of CNTs, which enhances the adsorptivity of the substrate and performs as an electron reservoir to trap electrons, thereby hindering the recombination of photogenerated electron–hole pairs. It is hoped that the current work on the facile synthesis of semiconductor In₂S₃–CNT nanocomposites can broaden the applications of semiconductor-carbon based composite photocatalysts in the field of photocatalytic selective organic transformations under mild conditions.