Molecular nanoprobes for thermal imaging of photoexcited metallic nanoparticles
5th Workshop on Quantitative Micro and Nano Thermal Imaging and Analysis, QMNTIA-2013, July 10-12, Reims, France.
Thermoplasmonic is a newly and very dynamic research field. The possibility to control and manipulate the thermal energy at the nanoscale will pave the way for numerous applications. Today, one of the challenges in thermoplasmonic is to measure and image the temperature generated around a single plasmonic nanostructure. Several approaches have been developed to address this issue [2, 3]. Here, we proposed a new approach based on the use of thermo-polymerizable formulations such as molecular nano-probes to characterize the local heat profile in the vicinity of an isolated gold nanoparticle during its excitation. For this we developed a set of thermopolymerizable formulations. Each one is characterized by a different and controlled polymerization temperature threshold (Tth), which can be adjusted by the weight percent of the initiator system. We studied the influence of various physical parameters on the extent of polymer around the nanoparticle. In particular, we show the possibility of imaging the heat distribution with a spatial resolution better than 40 nm. We also used a range of thermopolymerizable solution characterized by different threshold temperatures (Tth) to measure the local temperature around the nanoparticle. The results show that the temperature reached close to the photo-excited nanoparticle exceeds 180 ° C. Studies are underway to obtain both the extinction and near-field thermal signature of single and dimer gold nanoparticles at different wavelengths.