Plasmonic hot electrons-induced dissociation of SiH4 with nanoscale control

Abstract Localized surface plasmons (LSPs) confine light to subwavelength regions, enabling plasmon-mediated chemical reactions (PMCRs) with nanoscale precision. However, decoupling photothermal and nonthermal contributions within nanoscale region under femtosecond excitation remains challenging. In the present study the finite-difference time-domain (FDTD) simulations are integrated with a two-temperature model (TTM) to quantify electron and lattice temperature dynamics during LSP-driven SiH 4 dissociation in a bowtie nanostructure. And the three-dimensional thermal maps has been developed to capture the rapid, non-equilibrium rise of electron temperature (T e ) and its equilibration with the lattice (T l ). It is demonstrated that the silane decomposition proceeds predominantly via a hot-electron-mediated, nonthermal pathway, pinpointing a critical T e threshold for Si—H bond cleavage. This work establishes a quantitative framework for designing PMCR systems that exploit hot electrons for selective bond activation, offering a route to chemical reactions with true nanoscale control.