Hydrogen Production of Overall Water Splitting with Direct Z-Scheme Driven by Antimonene and Arsenide Nanoribbon Heterostructures: Insight from Electronic Properties and Carrier Nonadiabatic Dynamics

Abstract

Two nanoribbon heterostructures suitable for driving efficient direct Z-schemes of the photocatalytic overall water splitting for hydrogen production are screened out of 9 ones constructed from the edge-passivated antimonene (SbNR-X) and arsenide (AsNR-X, X= F, Cl, CN) nanoribbons. The solar-to-hydrogen (STH) efficiency and the Gibbs free energies (DGs) of the redox reactions at different sites are calculated to identify the preferable Z-schemes. Meanwhile, the transfer and recombination of the photogenerated carriers are explored by using nonadiabatic molecular dynamics (NAMD) simulations. The obtained band alignments and built-in electric fields of the two considered heterostructures can match the requirements of the photocatalytic Z-scheme, and the corresponding STH efficiencies can reach 15.04% and 30.53%, respectively. The oxidation evolution reactions can proceed spontaneously, and hydrogen evolution reactions are feasible in thermodynamics, respectively. The NAMD simulations show that the SbNR-CN/AsNR-CN nanoribbon heterostructure has faster interlayer recombination but slower transfer of the photogenerated electron from the SbNR-CN to AsNR-CN nanoribbons and transfer of the photogenerated hole along with the reversible direction, indicating it holds a higher carrier utilization rate. These findings confirm that the SbNR-CN/AsNR-CN nanoribbon heterostructure is a promising candidate for developing high STH efficiency materials with direct Z-schemes.

Keywords: interlayer transfer, Z-scheme, nanoribbon heterostructures, photocatalytic water splitting, nonadiabatic dynamics