Interestingly, the particles are still active photothermal nanoconverters when irradiated with a longer excitation wavelength (976 nm) due to their broad extinction spectrum. The temperature increment was 18.3K, which is lower than the increment obtained using the 808 nm laser (23.1K) at the same light intensity due to the different plasmon resonance conditions. The photostability of the gold solution is further examined by repeating the on/off cycle of the NIR laser irradiation.