Iron Incorporation-Induced Phosphorus Vacancies in MoP: A Dual-Functional Strategy Toward Efficient Solar Driven...

Area of Science:

• Materials Science
• Catalysis
• Photochemistry

Background:

• Internal modification of catalysts is key to improving photocatalytic hydrogen evolution.
• Doping and vacancy engineering synergistically regulate charge transfer dynamics.

Purpose of the Study:

• To investigate the mechanism of Fe-substitution-induced phosphorus vacancy (Vp) formation in MoP.
• To elucidate how Fe incorporation and Vp generation enhance photocatalytic hydrogen evolution.

Main Methods:

• Experimental synthesis of Fe-doped MoP (Fe-MoP).
• Characterization of catalyst properties.
• Photocatalytic hydrogen evolution rate measurements.
• Theoretical simulations (e.g., DFT) to understand electronic structure and charge dynamics.

Main Results:

• Fe incorporation into MoP preferentially substitutes Mo sites, inducing Vp formation.
• Fe 3d orbitals and Vp act as electron traps, while Mo atoms act as hole traps, optimizing charge separation.
• Fe-MoP-3 exhibits a 2.72-fold increase in hydrogen evolution rate (150.84 µmol/g) compared to pristine MoP (55.26 µmol/g).
• Increased catalyst surface area due to Fe incorporation provides more active sites.

Conclusions:

• Fe-induced Vp formation is a critical mechanism for enhancing photocatalytic hydrogen evolution in MoP.
• The synergistic effect of doping and vacancy engineering offers a pathway for designing efficient hydrogen evolution catalysts.
• This study provides fundamental insights into atomic substitution mechanisms for catalyst optimization.