A novel structure of quasi-monolayered NiCo-bimetal-phosphide for superior electrochemical performance

• Published in: Journal of energy chemistry 2022-11, Vol.74, p.203-211
• Main Authors: Zhao, Long, Wen, Ming, Tian, Yakun, Wu, Qingsheng, Fu, Yongqing
• Format: Article
• Language: English
• Subjects: 2D quasi-monolayer; Bimetal phosphide; Hydrogen evolution reaction; Oxygen evolution reaction; Ultrasonic-cavitation
• ISSN: 2095-4956
• DOI: 10.1016/j.jechem.2022.07.017

Two-dimensional quasi-monolayered NiCoP, synthesized by ultrasonic-cavitation and phase-transition process, can be applied as excellent bifunctional electrocatalyst for overall water splitting. [Display omitted] •Quasi-monolayered NiCoP gained by ultrasonic-cavitation and phase-transformation.•Rich edges and active sites created by abundant mesopores and larger surface areas.•R econfigured electronic structure and crystalline-amorphous enhance water splitting•Discover the e ffects of crystalline proportion on the electrolytic water. Bimetallic transition metal phosphides (TMPs) as potential candidates for superior electrochemical performance are still facing great challenges in the controllable preparation of two-dimensional (2D) structures with high aspect ratio. Herein, a novel structure of quasi-monolayered NiCo-bimetal-phosphide (NiCoP) has been designed and successfully synthesized by the newly developed process combined with ultrasonic-cavitation and phase-transition. This is the first time to break through the controllable preparation of 2D bimetal-phosphides with a thickness of 0.98 nm in sub-nanoscale. Based on the advantages of 2D quasi-monolayer structure with dense crystalline-amorphous interface and the reconfigured electronic structure between Niδ+/Coδ+ and Pδ−, the optimized Ni5%CoP exhibits an outstanding bifunctional performance for electrocatalyzing both hydrogen evolution reaction and oxygen evolution reaction in an alkaline medium. Ni5%CoP presents lower overpotentials and voltage of 84 mV & 259 mV and 1.48 V at the current density of 10 mA cm−2 for HER & OER and overall water splitting, respectively, which are superior to most other reported 2D bimetal-phosphides. This work provides a new strategy to optimize the performance of electrolytic water for bimetal-phosphates and it may be of significant value in extending the design of other ultrathin 2D structured catalysts.