Ti3C2 MXene co-catalyst on metal sulfide photo-absorbers for enhanced visible-light photocatalytic hydrogen production

TLDR

Scalable solar hydrogen production via photocatalytic water splitting requires highly active, stable, earth‑abundant co‑catalysts to replace expensive platinum. Using density functional theory, we designed and fabricated Ti₃C₂ MXene nanoparticles as a highly efficient co‑catalyst for photocatalytic hydrogen production. Ti₃C₂ nanoparticles, integrated with CdS via hydrothermal synthesis, achieve a record visible‑light photocatalytic hydrogen production rate of 14,342 µmol h⁻¹ g⁻¹ and 40.1 % quantum efficiency at 420 nm, owing to their favorable Fermi level, conductivity, and hydrogen evolution capacity, and they also act as efficient co‑catalysts on ZnS and ZnₓCd₁₋ₓS, illustrating the promise of earth‑abundant MXenes for high‑performance, low‑cost photocatalysts.

Abstract

Abstract Scalable and sustainable solar hydrogen production through photocatalytic water splitting requires highly active and stable earth-abundant co-catalysts to replace expensive and rare platinum. Here we employ density functional theory calculations to direct atomic-level exploration, design and fabrication of a MXene material, Ti 3 C 2 nanoparticles, as a highly efficient co-catalyst. Ti 3 C 2 nanoparticles are rationally integrated with cadmium sulfide via a hydrothermal strategy to induce a super high visible-light photocatalytic hydrogen production activity of 14,342 μmol h −1 g −1 and an apparent quantum efficiency of 40.1% at 420 nm. This high performance arises from the favourable Fermi level position, electrical conductivity and hydrogen evolution capacity of Ti 3 C 2 nanoparticles. Furthermore, Ti 3 C 2 nanoparticles also serve as an efficient co-catalyst on ZnS or Zn x Cd 1− x S. This work demonstrates the potential of earth-abundant MXene family materials to construct numerous high performance and low-cost photocatalysts/photoelectrodes.