Porous Ni5P4 as a promising cocatalyst for boosting the photocatalytic hydrogen evolution reaction performance

• Published in: Applied catalysis. B, Environmental Vol. 275; p. 119144
• Main Authors: Liu, Xin, Zhao, Yunxuan, Yang, Xiaofei, Liu, Qinqin, Yu, Xiaohui, Li, Youyong, Tang, Hua, Zhang, Tierui
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.10.2020; Elsevier BV
• Subjects: Carbon nitride; Carrier transport; Charge transport; Cocatalyst; Current carriers; Dianthus caryophyllus; Energy charge; HCN; Hydrogen evolution reactions; Hydrogen production; Nickel; Noble metals; Phosphides; Photocatalysis; Photocatalytic H2 evolution; Porous carnation-like Ni5P4; Self-assembly; Superstructures; Porous carnation-like Ni5P4; Photocatalytic H2 evolution; HCN; Cocatalyst
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2020.119144

[Display omitted] •Porous and carnation-like Ni5P4 was synthesized using phosphorization process.•Ni5P4 was used as cocatalyst to construct a Schottky-junction with g-C3N4.•Ni5P4 cocatalyst with lower adsorption behavior is favor for H2 production.•Ni5P4 cocatalyst can accelerate the separation of the light-induced carriers. Nonmetallic cocatalysts have demonstrated unprecedented potential for accelerating photocatalytic hydrogen evolution reaction (HER). In this study, a nickel phosphide compound, namely Ni5P4, with porous carnation-like superstructure has been target-synthesized and then employed as HER cocatalyst to in-situ build a hybrid with protonated g-C3N4 nanosheets via an electrostatic self-assembly method. Owing to the synergistic advantages of the excellent metallic conductivity and porous carnation-like superstructure of Ni5P4, the as-obtained HCN/Ni5P4 Schottky-junction with abundant active sites, low H* atom adsorption energy and efficient charge carrier transport channel, affords the photocatalytic H2 production rate of 1157.5 μmol g−1 h−1 when exposed to visible light (λ > 420 nm). This photocatalytic H2 production rate was much higher than those of the corresponding reference cocatalysts, namely Ni2P and NiS2 (169.1 and 593.1 μmol g−1 h−1, respectively), both of which were derived from the same Ni(OH)2 precursor. This study provides a new idea for the design of highly active noble-metal-free materials for the photocatalytic HER.