Vacancy-mediated transition metals as efficient electrocatalysts for water splitting.

Area of Science:

• Materials Science
• Electrochemistry
• Computational Chemistry

Background:

• Water splitting using renewable electricity is crucial for sustainable hydrogen production.
• Developing efficient, cost-effective, and durable electrocatalysts is a key challenge for industrial applications.

Purpose of the Study:

• To design and screen M@CuS catalysts with excellent catalytic activity for water splitting.
• To investigate the potential of vacancy engineering and metal doping in enhancing catalyst performance.

Main Methods:

• Density functional theory (DFT) calculations were employed to design and screen M@CuS catalysts.
• The stability and active centers of transition metal (TM) single atoms anchored by CuS vacancies were analyzed.
• Hydrogen adsorption free energies (ΔG_H*) and oxygen evolution reaction (OER) overpotentials were calculated.

Main Results:

• Ti@CuS and Co@CuS demonstrated exceptional performance for the hydrogen evolution reaction (HER), with ΔG_H* values of 0.01 eV and -0.03 eV, respectively.
• The HER process for Ti@CuS was found to be governed by the Heyrovsky mechanism.
• Co@CuS exhibited superior catalytic activity for the oxygen evolution reaction (OER) with a low overpotential of 0.41 V, indicating its potential as a bifunctional catalyst.

Conclusions:

• The proposed strategy of vacancy engineering and metal doping successfully yielded highly efficient electrocatalysts for water splitting.
• Ti@CuS and Co@CuS are promising candidates for efficient HER and OER, respectively.
• This work offers a novel concept for designing advanced catalysts in various catalytic fields.