Metal–support interactions in Pt-embedded porous Fe2P nanorods for efficient hydrogen production

Abstract

Metal–support-interactions (MSIs) are critical in catalyst design and optimization toward enhancing the solar-driven photocatalytic hydrogen-evolution-reaction (HER). Transition metal phosphates (TMPs) have been predicted as promising catalysts for the photocatalytic HER owing to their high chemical diversity and superior optical properties. However, it has been found that TMPs suffer from strong hydrogen adsorption and weak desorption, leading to unbalanced hydrogen absorption/desorption behavior and a sluggish photocatalytic HER process. Herein, an MSI was delicately designed by embedding Pt-nanoparticles into porous iron phosphide nanorods (MSI Pt–Fe₂P) via a facile metal–organic-framework (MOF)-derived approach assisted by phosphating treatment. Experimental characterization and theoretical calculations disclose that the formation of MSI resulted in regulating the electronic structure and balancing the hydrogen absorption/desorption behavior of Fe₂P. Benefiting from the alteration of the electronic structure, the resultant Pt–Fe₂P featuring an MSI enables a remarkable photocatalytic HER rate of 6 mmol g⁻¹ h⁻¹ with a high apparent quantum efficiency of 20% at 500 nm wavelength. This finding may pave the way for developing more efficient TMP-based catalysts for various solar energy applications.