Electrode

Organic chemistry

Nickel

Hydrogen

Crystallography

Vacancy defect

Catalysis

Physical chemistry

Overpotential

Hydrogen production

Inorganic chemistry

Chemistry

Metallurgy

Materials science

Phosphide

Nickel sulfide

Platinum

Electrochemistry

Biochemistry

Non-blocking I/O

Advanced Energy Materials

Developing low‐cost and high‐efficiency catalysts for sustainable hydrogen production through electrocatalytic hydrogen evolution reaction (HER) is crucial yet remains challenging. Here, a strategy is proposed to fill Ni‐vacancy (Ni v ) sites of dual‐deficient NiO (D‐NiO‐Pt) deliberately created by Ar plasma with homogeneously distributed Pt atoms driven by oxygen vacancies (O v ). The incorporated Pt atoms filling the Ni v reduce the formation energy to increase crystal stability, and subsequently combine with additional O v to tune the electronic structure of the surrounding Ni sites. Thus, a more ideal hydrogen adsorption free energy (Δ G H* ) closer to 0 of Ni sites and Pt sites can be achieved. As a result, the D‐NiO‐Pt electrode achieves superior mass activity of ≈1600 mA mg −1 (normalized by platinum) and nearly negligible loss of activity during long‐term operation, which is much better than as‐prepared Pt‐containing NiO catalysts without plasma treatment. A low overpotential of 20 mV is required for the D‐NiO‐Pt at 10 mA cm −2 in alkaline HER, outperforming that of the commercial Pt/C. In addition, the universal access to the other Ni‐based compounds including nickel phosphide (Ni 2 P), nickel sulfide (Ni 0.96 S), and nickel selenide (NiSe 2 ) is also demonstrated by employing a vacancy‐driven Pt filling mechanism.

Atomic‐Level Platinum Filling into Ni‐Vacancies of Dual‐Deficient NiO for Boosting Electrocatalytic Hydrogen Evolution