Hierarchical microarchitectures of AgGa1−xInxS2: Long chain alcohol assisted synthesis, band gap tailoring and photocatalytic activities of hydrogen generation

Abstract

An enhanced visible-light-driven photocatalyst, AgGa1−xInxS2, was prepared by a facile long chain alcohol assisted hydrothermal route. Phase structures, morphologies, optical properties, energy level and specific surface areas of the products were characterized by X-ray diffraction, scanning electron microscope, UV–vis spectra and BET analysis. The obtained products show unique hierarchical microarchitectures which were fabricated by micro-sphere and nano-sheets. The introducing of long chain alcohol (pentanol and heptanol) was investigated to be crucial for the forming of hierarchical microarchitectures. On the other hand, the band gap energy of AgGa1−xInxS2 (x = 0–1) estimated from the onset of absorption edge was found to be reduced from 2.71 eV (x = 0) to 1.93 eV (x = 1) by indium substitution. The photocatalytic activity for hydrogen evolution was investigated under visible light irradiation (λ > 400 nm). The rate of hydrogen evolution reached up to 813 μmol/h when the amount of In (x) was 0.1 and the roles of long chain alcohol and Ga/In were also carefully investigated.