A novel amorphous/crystalline RuTe heterostructure catalyst for efficient and sustainable hydrogen production

Abstract

The growing energy crisis and environmental concerns demand sustainable energy solutions, with hydrogen emerging as a promising alternative due to its zero emissions and high energy density. While water electrolysis is ideal and sustainable approach for hydrogen production, it requires efficient electrocatalysts for the hydrogen evolution reaction (HER). Platinum (Pt) is highly effective but costly and less active in alkaline media, prompting research into other alternatives. Ruthenium (Ru), particularly in the form of RuTe₂, has emerged as a promising alternative due to its better hydrolytic dissociation capacity and lower cost. This study introduces an amorphous/crystalline heterostructure catalyst (a-RuTe@c-Te) for enhanced alkaline HER. The catalyst was synthesized through a green method, producing a porous amorphous RuTe layer on the crystalline Te nanotubes. The a-RuTe@c-Te catalyst demonstrated superior HER activity, with a low overpotential of 27 mV at 10 mA cm⁻² in 1 M KOH, outperforming commercial Pt/C and crystalline RuTe₂. The density functional theory (DFT) calculations reveal that the d-band center of a-RuTe@c-Te was pulled up closer to Fermi level by the electron enrichments at the amorphous/crystalline interface, leading to a reduced electron filling in the antibonding orbitals, thus increasing the hydrogen adsorption strength. This work offers a promising approach for designing high-performance HER catalysts, advancing sustainable energy applications.