Tuning Catalytic Activity in Nitride Perovskite Through Strain-Induced Rashba Spin Splitting Manipulation

Rashba spin splitting is an emerging phenomenon originating from the synergistic effect of relativistic spin–orbit coupling (SOC) due to the presence of a heavy constituent element and the noncentrosymmetric crystal structure. We recently observed Rashba spin splitting in the rare nitride perovskite CeNbN3. This work explores how tuning the Rashba spin splitting strength can enhance photocatalytic water splitting and hydrogen evolution reaction (HER) activity. Based on our electronic structure calculations, we have observed the fine-tuning of Rashba spin splitting in CeNbN3 under the influence of compressive strain and the corresponding impact on HER activity. The evolution of electronic band structure, Rashba spin splitting strength, and spin texture under compressive strain corresponds well with the hydrogen adsorption free energy determined from the constructed reaction coordinate mapping of the HER mechanism. The strength of spin splitting shows a correlation with improved HER activity, which is in line with the influence of the Rashba effect.