Intrinsic Phonons as a Dynamic Control Knob for Catalytic Reactivity in 2D Materials

Catalytic activity is conventionally understood in terms of static electronic structure descriptors, with lattice vibrations treated as a passive background. Here we show that intrinsic phonon modes can serve as an active and selective control knob for catalytic reactivity in 2D materials. Using density functional theory, we demonstrate that mode-specific lattice excitations in transition metal dichalcogenides dynamically modulate their electronic structure, inducing direct-indirect bandgap transitions and substantial bandgap renormalization. In Janus WSSe, excitation of the A1 2 mode reduces the bandgap to 0.93 eV, significantly enhancing carrier transport. More importantly, these phonon-induced lattice distortions systematically tune adsorption energetics and reaction pathways. Using the oxygen evolution reaction as a model system, we find that phonon activation lowers the overpotential by up to 17%, arising from weakened adsorption of key intermediates. Crystal orbital Hamilton population and p-band center analyses reveal that this effect originates from phonon-driven modulation of orbital hybridization and bonding strength. Our results establish a dynamic, mode-selective paradigm for controlling catalytic processes via intrinsic lattice degrees of freedom, opening a route toward phonon-engineered electrocatalysis beyond static materials design.