Bio-inspired design of NiFeP nanoparticles embedded in (N,P) co-doped carbon for boosting overall water splitting

• Published in: Dalton transactions : an international journal of inorganic chemistry 2023-05, Vol.52 (2), p.686-6869
• Main Authors: Zhang, Xiangrui, Shi, Xue-Rong, Wang, Peijie, Bao, Zhiyu, Huang, Mengru, Xu, Yanan, Xu, Shusheng
• Format: Article
• Language: English
• Subjects: Biomimetics; Carbon; Carbon nanotubes; Current density; Electrocatalysts; Electrolysis; First principles; Hydrogen evolution reactions; Nanoparticles; Oxygen evolution reactions; Phosphides; Seawater; Strong interactions (field theory); Water splitting
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/d3dt00583f

The design and synthesis of cost-effective and stable bifunctional electrocatalysts for water splitting via a green and sustainable fabrication way remain a challenging problem. Herein, a bio-inspired method was used to synthesize NiFeP nanoparticles embedded in (N,P) co-doped carbon with the added carbon nanotubes. The obtained Ni 0.8 Fe 0.2 P-C catalyst displayed excellent hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) performances in both alkaline and alkaline simulated seawater solutions. The optimal Ni 0.8 Fe 0.2 P-C/NF only needs overpotentials of 45 and 242 mV to reach the current density of 10 mA cm −2 under HER and OER working conditions in 1.0 M KOH solution, respectively. First-principles calculations revealed the presence of a strong interaction between the carbon layer and metal phosphide nanoparticles. Benefiting from this and carbon nanotubes modification, the fabricated Ni 0.8 Fe 0.2 P-C presents impressive stability, working continuously for 100 h without collapse. A low alkaline cell voltage of 1.56 V for the assembled Ni 0.8 Fe 0.2 P-C/NF//Ni 0.8 Fe 0.2 P-C/NF electrocatalyzer could afford a current density of 10 mA cm −2 . Moreover, when integrated with a photovoltaic device, the bifunctional Ni 0.8 Fe 0.2 P-C electrocatalyst demonstrates application potential for sustainable solar-driven water electrolysis. Inspired by natural biomass mineralization, we synthesized CNTs-modified NiFeP embedded in N and P co-doped porous carbon materials using N-containing sugar (chitosan), biomass P source (phytic acid), metal salts, and CNTs as raw materials.