Carbon encapsulation strategy of Ni co-catalyst: Highly efficient and stable Ni@C/CdS nanocomposite photocatalyst for hydrogen production under visible light

Abstract

Carbon encapsulation strategy of Ni co-catalyst is applied to the fabrication of novel carbon-coated Ni (Ni@C)/CdS nanocomposite photocatalyst with high efficiency and good stability via a facile solvothermal process by using a pre-prepared Ni@C as a starting material. It is found that the metallic Ni nanoparticles encapsulated in the graphite-like carbon shells show a high chemical and thermal stability, and the resultant Ni@C/CdS nanocomposite shows an average photocatalytic H2-production activity of 622.7μmolh−1 during 5-h visible-light irradiation and an apparent quantum yield up to ca. 20.5% under 420nm monochromatic light irradiation. The metallic Ni in Ni@C acted as co-catalyst while the graphite-like carbon as CdS nanoparticles’ support and electron acceptor, which resulting in the efficient charge separation, and then the enhanced photoactivity and stability for H2 production as compared to the pristine CdS nanoparticles. The present novel carbon encapsulation strategy of Ni co-catalyst can shed light on the fabrication of new cheap photocatalyst with excellent photoactivity and stability for H2 production.