Boosting hot electrons transfer via laser-induced atomic redistribution for plasmon-enhanced nitroreduction and single-particle study

Plasmonic nanostructures with strong light absorption and high catalytic activity are ideal platform to realize efficient light-driven catalysis. This work developed a laser-induced-reshaping route (pulse width 10 ns, wavelength 1064 nm) to improve the efficiency of energy transfer between non-plasmonic material (Pt) and plasmonic Au nanorods (NRs). The catalytic performance for 4-nitrophenol (4-NP) hydrogenation was increased by 2-fold using laser-modified Pt-Au NRs (L-Pt-Au NRs) compared to original Pt-Au NRs. Very impressively, the relationship between laser-induced reshaping and resulting optical properties was investigated at single-particle level. Finite difference time domain (FDTD) simulation and single-particle photoluminescence (PL) quenching (48.6%) after laser induced reshaping, indicated the redistributed Pt atoms on Au NRs surfaces largely promoted hot electron transfer and decreased radiative photon re-emission. Further, the mechanism of plasmon-enhanced nitroreduction was studied in situ at the single-particle level. This work provides insight into the design and application of plasmonic nanostructures at single-particle level.