Numerical simulations generally cannot capture the impact of nanoparticle surface chemistry, such as ligand coverage and crystallographic facets. Experimental measurements of hot carrier generation dynamics with sub-particle spatial resolution would both enhance fundamental understanding toward rational photocatalyst design and improve numerical modeling by providing validated input parameters. In situ transmission electron microscopy (TEM) has been demonstrated as a unique approach for real time imaging of nanomaterials in realistic environmental conditions with atomic to nanometer spatial resolution. Liquid phase TEM (LP-TEM) can visualize nanometer-scale phenomena in liquid in real time, including deposition of secondary metals on seed nanoparticles. The TEM electron beam during LP-TEM acts as both the stimulus for metal deposition and the imaging probe. Prior work has indicated that the TEM electron beam can serve as an evanescent white light source that generates surface plasmons in metallic nanostructures, suggesting the possibility of leveraging LP-TEM to investigate LSPR-mediated redox processes even without highly specialized TEM apparatuses. The large intensities and plasmon excitation cross sections associated with the TEM beam may expedite experimental timeframes compared to optical excitation. Prior work has utilized the electron beam in LP-TEM to induce shape transformations in colloidal silver nanoparticles. However, both LSPR mediated chemistry and electron radiolysis can drive aqueous phase redox chemistry during LP-TEM, making it difficult to disambiguate the precise reaction mechanism. Radiation chemistry often dominates reaction pathways due to the production of strongly reactive oxidizing and reducing radicals. Recent work by Chen et al. found Ag deposition on plasmonic gold nanorods (AuNRs) in water during LP-TEM was consistent with ligand-mediated chemical reduction by aqueous electrons and hydrogen radicals, as opposed to LSPR hot electron driven reactions. Dynamic processes studied using LP-TEM are commonly stimulated in situ by reactive chemical species formed during electron beam solvent radiolysis. Solvated electrons (es -), hydrogen radicals (H • ), and hydroxyl radicals (OH • ) are powerful reducing and oxidizing species able to dominate metal ion/metal redox processes during LP-TEM, prohibiting isolating and observing metal reduction by plasmonic hot electrons. Here we demonstrate the use of a radiation resistant solvent mixture containing toluene and isopropanol to observe in situ plasmonic hot carrier-mediated Ag deposition onto AuNRs with LP-TEM. Silver deposition served here as a directly observable probe reaction to quantify the spatial dynamics of plasmonic hot carriers across the AuNR surface. Toluene was chosen as the primary solvent to minimize generation of reducing radicals and ionic species, while isopropanol (IPA) was included as a plasmonic hot hole and OH • scavenger and to solubilize the silver precursor. LP-TEM observations showed enhanced metal deposition at predicted transverse LSPR hotspots, which accorded with particle morphologies obtained by bench top white light illumination. Control experiments demonstrated that radiolysis species did not significantly contribute to particle reshaping or metal deposition during LP-TEM. Relationships between nanorod growth dynamics, electron beam flux, and AuNR orientation were consistent with plasmon resonance simulations. Overall, this work opens the door for utilizing LP-TEM and radiation resistant solvents for real time nanoscale visualization of plasmon-driven phenomena in the liquid phase. While silver deposition was used as the probe reaction here, we expect this approach can be extended to other plasmon hot carrier driven reactions with gaseous products that can be visualized with TEM, such as alcohol oxidation, CO2 reduction, or ammonia synthesis. 2