Correlation Between Rashba Spin Splitting and HER Activity Enhancement in Two-Dimensional Layered Nanostructures

We address the fundamentals and possible implications of Rashba phenomena particularly for heavy element-containing non-centrosymmetric ultrathin two-dimensional nanostructured catalytic materials. It aims to shed light on the application paradigm of these exciting phenomena in the field of catalytic reaction mechanism, specially the photocatalytic water splitting which strongly depends on HER. The experimental realization along with the theoretical prediction of these phenomena in the emerging family of 2D materials could open up a new direction for modulating the charge carrier recombination probability. The influence of external parameters like hydrostatic pressure, uni and bi-axial strain are expcted to change the Rashba splitting factor, which essentially suppresses the recombination rate. Our work would provide a possible roadmap of materials design and the effect of external stimuli on the plethora of 2D materials for extensive energy scavenging with the focus on catalytic reaction mechanism. We have employed electronic structure calculations along with Spin-Orbit-Coupling to envisage the spin-splitting qualitatively and quantitatively from the bandstructure and spin-texture. Our atomistic modelling entails better understanding of the HER and make reliable advancements to expanding field of water splitting. Our aim is to create intermediate electronic states through Rashba band splitting, where electrons can stay and subsequently start HER mechanism. Therefore, we have performed the adsorption free energy analysis to form the reaction coordinate that maps all the reaction intermediates in order to find the corresponding overpotential along with the band structures of novel 2D materials to envisage the Rashba like band splitting through the external strain.