Marigold shaped mesoporous composites Bi2S3/Ni(OH)2 with n-n heterojunction for high efficiency photocatalytic hydrogen production from water decomposition

Abstract

The abundant active sites of catalysts are effective means to regulate the directional migration of photogenic carriers and improve the catalytic activity of photocatalysts. The Ni(OH)2 with three-dimensional nano-flower structure was successfully prepared. The three-dimensional nanofloral structure weakened the van der Waals forces between the nanosheets, inhibited the interlamellar superposition, and thus exposed more active sites to improve the activity of photocatalytic decomposition water to hydrogen production. When the addition amount of Bi2S3 is 10%, a solution of triethanolamine at pH 10 after 5 h of simulated sunlight irradiation, in the dye sensitization system the hydrogen production amount of the composite catalyst Bi2S3/Ni(OH)2 is 119 μmol, which is about 12 times that of pure Bi2S3 (12 μmol) and about 2.5 times that of pure Ni(OH)2 (48 μmol). Microstructure, optical, physicochemical properties and structural tests of the photocatalysts are investigated by Brunauer-Emmett-Teller (BET), Ultraviolet–visible (UV–Visible), Photoluminescence (PL) and Electrochemical techniques. Results prove that Bi2S3/Ni(OH)2–10% nanocomposite catalysts increase specific surface area and visible light utilization. The n-n heterogeneous junction is formed, which reduces the composite rate of electrons and holes, and improves photocatalytic split of water to produce hydrogen under visible light irradiation.