The plasmon-induced photothermal
effect is often regarded
as one
of the most intriguing features of Au nanorods (AuNRs). The spectral
matching of absorption and excitation determines the optical absorption
quantity and the photothermal conversion efficiency, which is essential
for practical applications. Although the dimensional tunability of
monodisperse AuNRs has already been accessible, the fine-tuning of
AuNRs with longitudinal surface plasmon resonance (LSPR) at a desired
wavelength to match the excitation is still challenging because of
inferior reproducibility and synthetic complexity. In this work, using
hydroquinone as both a cosurfactant and a reductant, we propose a
synthetic strategy toward AuNRs with excellent linear tunability of
LSPR peaks from 530 to 1200 nm via simply altering the dosage of silver
nitrate. Given that the laser wavelength for ignition is 1064 nm,
the LSPR wavelength of AuNRs could be exactly controlled at 1064 nm
for maximum photothermal performance. Afterward, the as-prepared AuNRs
were coated with a dendritic mesoporous silica shell for plasmonic
stability and loading explosive molecules. As a proof of concept,
the laser ignitability could be achieved only in the presence of AuNRs
with LSPR wavelength approaching 1064 nm, highlighting the importance
of spectral matching in photothermal conversion-assisted laser ignition.