Dye-sensitized photocatalytic hydrogen evolution by using copper-based ternary refractory metal chalcogenides. (11th June 2020) - Genc, Eminegul
Abstract: The exploration of photocatalytic transformation of solar energy into H2 through water splitting is an important direction towards sustainable and non-polluting energy in order to cover energy necessity partially. Ternary transition metal chalcogenides have been attracted attention among the other chalcogenides due to their potential applications in the photocatalytic and electrocatalytic hydrogen evolution. Herein, Cu2 WS4 nanocubes and Cu2 WSe4 nanosheets have been synthesized through a facile hot-injection method to benefit from the advantages such as minimizing the required pressure and reaction time by this technique. The photocatalytic hydrogen evolution activities of Cu2 WS4 and Cu2 WSe4 have been investigated under the visible light irradiation by using eosin-Y (EY) dye and triethanolamine (TEOA) as a photosensitizer and an electron donor, respectively. Cu2 WS4 nanocubes have exhibited higher photocatalytic activity and stability than Cu2 WSe4 nanosheets. The photocatalytic HER rates of Cu2 WS4 and Cu2 WSe4 have been determined as 1260 μmol g −1 h −1 and 861 μmol g −1 h −1, respectively. Photocatalytic HER activities were figured out in the order of Cu2 WS4 > Cu2 WSe4 which could be attributed to differences between proton reduction potential and the conduction band energy levels. Graphical abstract: Image 1 Highlights: Photocatalytic HER rates of Cu2 WS4 and Cu2 WSe4 are compared for the first time. Cu2 WS4 shows higher photocatalytic activity and stability than Cu2 WSe4 . Photoactivity differences are explained by electrochemical energy levels.