Physicochemical properties of core/shell structured pyrite FeS2/anatase TiO2 composites and their photocatalytic hydrogen production performances

A new photocatalytic system using anatase TiO2 loaded onto pyrite FeS2 (FeS2/TiO2) was developed to enhance the production of hydrogen. The FeS2 (3.0, 5.0, 10.0, and 15.0 wt-%)/TiO2 particles in SEM photos showed a core/shell structure composed of pyrite FeS2 with a grape-like morphology of length of ∼1.0 μm and anatase TiO2 of diameter <50 nm. The evolution of H2 by methanol/water (1:1) photo splitting over FeS2/TiO2 in a liquid system was enhanced as compared with that obtained using pure TiO2 and FeS2. In particular, 9.8 mmol of H2 gas was produced in 10 h when 0.5 g of a 10.0 wt-% FeS2/TiO2 core/shell composite was used. Hydrogen production was increased by adding KOH electrolyte to 11.2 mmol. On the basis of cyclic voltammetry (CV) and UV–visible spectra results, this photoactivity of the FeS2/TiO2 composite was attributed to a shorter band gap than those of pure TiO2 and FeS2.