Cooperative non-covalent interactions-directed the supramolecular self-assembly and its derivative for bifunctional water electrocatalysis

• Published in: Journal of alloys and compounds Vol. 930; p. 167460
• Main Authors: Che, Peng-Cheng, Li, Junji, Gong, Yuxiao, Xu, Lian-Hua, Shan, Dan
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 05.01.2023; Elsevier BV
• Subjects: Carbon; Chemical bonds; Chemical synthesis; Co2P nanoparticles; Cobalt; Cooperative non-covalent interactions; Electrocatalysis; Electrocatalysts; High temperature; Hydrogen atoms; Hydrogen bonding; Hydrogen evolution reaction (HER); Melamine; Nanoparticles; Oxygen evolution reaction (OER); Oxygen evolution reactions; Phosphides; Phytic acid; Precursors; Self-assembly; Supramolecular self-assembly; Transition metals; Water splitting; Hydrogen evolution reaction (HER); Cooperative non-covalent interactions; Supramolecular self-assembly; Co2P nanoparticles; Oxygen evolution reaction (OER)
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2022.167460

The highly dispersed transition metal phosphides have gradually become viable electrocatalysts candidates for water splitting due to their high efficiency, ease of availability, and good stability. Herein, a novel electrocatalyst composed of Co2P embedded in N and P co-doped carbon (Co2P @ NPC) was designed using a tuned self-assembly strategy and high-temperature calcination. The former strategy was employed to prepare a supramolecular precursor self-assembled via cooperative non-covalent interactions. Specifically, Co2+ ions were introduced into the preorganized phytic acid (PA)-melamine (MA) hydrogen-bonded system, and competitively substituted hydrogen atoms to form coordinate bonds with PA. The Co2P @ NPC catalyst synthesized from the 800 ℃-calcinated precursor exhibited a well-modulated structure of carbon-entrapping Co2P nanoparticles, which promoted its efficient bifunctional electrocatalysis for hydrogen and oxygen evolution reactions (HER and OER). To achieve a current density of 10 mA cm−2, the electrocatalyst only required overpotentials of 288 mV for HER and 476 mV for OER. [Display omitted] •The self-assembly of PA, MA and Co2+ was directed by cooperative non-covalent interactions, using DMF as solvent.•Co2+ was confined into MA-PA via coordination, benefit for the high dispersion of the resultant active sites.•MA aggregates serve as N- and C- sources and prevent the agglomeration of metal active sites during carbonization.•Co2P @ NPC exhibited efficient bifunctional electrocatalytic activities for HER and OER.