Phase‐Controlled Synthesis of Nickel Phosphide Nanocrystals and Their Electrocatalytic Performance for the Hydrogen Evolution Reaction

• Published in: Chemistry : a European journal Vol. 24; no. 45; pp. 11748 - 11754
• Main Authors: Li, Huiming, Lu, Siqi, Sun, Jingyao, Pei, Jiajing, Liu, Di, Xue, Yanrong, Mao, Junjie, Zhu, Wei, Zhuang, Zhongbin
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 09-08-2018
• Subjects: Catalysis; Catalytic activity; Chemical synthesis; Chemistry; Crystallization; Crystals; electrochemistry; heterogeneous catalysis; hydrogen evolution reaction; Hydrogen evolution reactions; Nanocrystals; Nickel; nickel phosphides nanoparticles; Organic chemistry; phase control; Phosphides
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201801964

The phase of nanocrystals has a key role in the modulation of catalytic properties. Uniform and well‐crystallized nickel phosphide nanocrystals with controlled phases (Ni5P4, Ni2P, and Ni12P5) and narrow size distributions are synthesized by a wet chemical method. The phases of the as‐synthesized nickel phosphide nanocrystals are controlled by the P/Ni precursor molar ratio, heating process, and time of reaction. Rarely reported nearly monodisperse 5.6 nm Ni5P4 nanocrystals are successfully synthesized and show superior hydrogen evolution reaction (HER) activity. Only a low overpotential of 103 mV is required to achieve the HER current of 10 mA cm−2 at a low catalyst loading of 0.12 mg cm−2. The high HER activity is attributed to the high quality of the as‐obtained Ni5P4 nanocrystals, which have the electronic effect from the Ni5P4 phase and also high surface area owing to the small particle size. A systematic study of the controlled synthesis of nickel phosphide nanocrystals is shown in this paper, and the HER catalytic activity is improved through the phase‐ and size‐controlled synthesis of nanocrystals.
Nickel phosphide nanocrystals: High‐quality nickel phosphide nanocrystals with controlled phases (Ni5P4, Ni2P, and Ni12P5) and narrow size distributions are synthesized. The rarely reported nearly monodisperse 5.6 nm Ni5P4 nanocrystals show superior hydrogen evolution reaction (HER) activity.