Highly Efficient Water Splitting Catalyst Composed of N,P-Doped Porous Carbon Decorated with Surface P-Enriched Ni₂P Nanoparticles

A non-noble-metal hybrid catalyst (Ni₂P/NPC-P), composed of N,P-doped porous carbon decorated with surface P-enriched Ni₂P nanoparticles, is developed to address the urgent challenges associated with mass production of clean hydrogen fuel. The synthesis features one-pot pyrolysis of inexpensive fluid catalytic cracking slurry, graphitic carbon nitride, and inorganic salts, followed by a feasible surface phosphidation process. As a non-noble metal catalyst, Ni₂P/NPC-P demonstrates excellent performance in hydrogen evolution reaction in alkaline electrolytes with a low overpotential of 73 mV at a current density of 10 mA cm^-2 (η₁₀) and a small Tafel slope of 56 mV dec^-1, meanwhile exhibits durability with no significant η₁₀ change after 2000 catalytic cycles. Theoretical calculation reveals that the negatively charged P-enriched surface accelerated the rate-determining transformation and desorption of OH*. In overall water splitting, the electrocatalyst achieves a low η₁₀ of 1.633 V, promising its potential in the cost-effective mass production of hydrogen fuel.