Molten state synthesis of nickel phosphides: mechanism and composition-activity correlation for electrochemical applications. Issue 48 (3rd December 2021)

• Record Type: Journal Article
• Authors: Geva, Rotem; Levy, Natasha Ronith; Tzadikov, Jonathan; Cohen, Reut; Weitman, Michal; Xing, Lidan; Abisdris, Liel; Barrio, Jesús; Xia, Jiawei; Volokh, Michael; Ein-Eli, Yair; Shalom, Menny
• Is Part Of: Journal of materials chemistry. Volume 9:Issue 48(2021)
• Page Start: 27629
• Page End: 27638
• Publication Date: 2021-12-03
• Subjects: Materials -- Research -- Periodicals; Chemistry, Analytic -- Periodicals; Environmental sciences -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d1ta08455k
• Languages: English
• ISSNs: 2050-7488

Abstract

Abstract : A straightforward, benign, scalable and low-cost molten-state synthesis of nickel phosphides with tunable phase composition, applied both as electrocatalysts for hydrogen evolution reaction and as anode materials for Li-ion batteries. Abstract : Nickel phosphides are highly attractive low-cost (electro)catalysts, thanks to their unique electronic structure, versatile phase diagram, and chemical stability. Herein, we describe a single-step, simple, and scalable synthesis of nickel phosphides, with good control over phase composition, size, and catalytic activity, by a direct thermal reaction of nickel nitrate hexahydrate and triphenylphosphine (PPh3 ). Advanced analytic tools combined with theoretical calculations reveal that upon heating, nickel ions are dissolved and coordinated by PPh3, enabling the synthesis of fine-tuned particles, with nickel phosphide phases ranging from Ni3 P to Ni2 P. The new synthetic method enables comprehending the correlation between phase composition and the phosphides' catalytic activity. This work shows a clear composition-activity trend of the optimized nickel phosphides both as electrocatalysts for the hydrogen evolution reaction in acidic media and as anode materials in Li-ion batteries.