Synthesis and peferentially loading of nickel nanoparticle on CdS surface and its photocatalytic performance for hydrogen evolution under visible light

Ni nanoparticles were prepared via chemical reduction of NiCl2 by NaBH4 in the presence of polyvinlylpyrolidone (PVP), and loaded on the surface of CdS by photo-induced electrons while water splitting reaction occurred simultaneously. Resultant Ni/CdS was characterized by high-resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, ultraviolet–visible light diffuse reflectance spectrometry, and photoluminescence spectrometry. It was found that as-prepared Ni nanoparticles are about 3 nm, and preferentially deposited on (1 0 0), (0 0 2), and (1 0 1) crystal planes of CdS. Meanwhile, loading nickel decreases the photoluminescence intensity of CdS, which means nickel functions as the trapper of photo-generated electrons. Therefore, nano-Ni/CdS photocatalyst with a Ni loading of 2.5% possesses the best visible-light catalytic activity for water splitting-hydrogen evolution and provides a hydrogen production rate of up to 9050 μmol h−1 g−1, while it exhibits stabilized activity towards H2 evolution as well.