Simulation of the spectral properties and photothermal effects of homogeneously dispersed solution of gold nanorods

The photothermal effect influences the sensing performance of gold nanorods (AuNRs) in solution, mainly in terms of sensitivity and detection accuracy. However, less work has been done to investigate this influence by using numerical simulation methods. A model for calculating the extinction curve of uniformly dispersed AuNRs in aqueous solution was established using the finite element method, and the influence of photothermal effect on the sensing performance of AuNRs solution is investigated by combining with density functional theory (DFT). The sensitivity and detection accuracy of AuNRs solutions were investigated by considering the refractive index change and the thermal expansion effect caused by the photothermal effect. It demonstrated that the refractive index change has a great influence on the sensitivity and detection accuracy, while the thermal expansion effect only affects the detection accuracy. The developed numerical simulation model for the study of the photothermal effect is expected to provide meaningful guidance for the development of the AuNRs solution sensors.