Radical clock thermometer to investigate the events occurring during the irradiation of various nanoparticles

A few years ago, we showed that the homolysis of alkoxyamines R1R2NOR3 into nitroxyl R1R2NO• and in alkyl R3• occurred quickly at room temperature in the presence of irradiated gold nanoparticles AuNP (i.e., Surface Plasmon Resonance) whereas such molecules are stable for decades at room temperature.1 That result has been applied to develop the Plasmon-Initiated-Nitroxide Mediated Polymerization.1 In parallel, we developed the activation of the homolysis of the alkoxyamines in the presence of iron oxide nanoparticles IONP under Alternated Magnetic Field and observed an efficient homolysis at temperatures of the solution lower than reported by the thermal camera.2 Furthermore, the activation of e mixture of two different alkoxyamines in the present of Prussian Blue nanoparticles PBNP irradiated in NIR showed that the homolysis rate kd of the alkoxyamine are those expected for a given temperature and that temperature is higher than the one recorded by thermal camera.3 Hence using kinetics and Arrhénius equation it is possible to get back information on the temperature either at the surface of the NP or in its corona.3 We developed the first radical clock thermometer based on the radical generation using the homolysis of alkoxyamines. Moreover, these alkoxyamines can also probe the occurrence of various mechanisms involved in the energy released by various NP, i.e., thermal effect vs hot holes vs hot electrons vs orbital interactions for the Surface Plasmon Resonance 4 or electrical field activation vs “hot” electron vs orbital interaction vs thermal effect for the NIR irradiation of PBNP.3

1 Guselnikova, O.; Marque, S. R. A.; Tretyakov, E.; Mares, D.; Jerabek, V.; Audran, G.; Joly, J.-P.; Trusova, M.; Švorčik, V.; Lyutakov, O.; Postnikov, P. J. Mat. Chem. A 2019, 7, 20, 12414-12419.

2 Bouvet, B.; Sene, S.; Félix, G.; Havot, J.; Audran, A.; Marque, S. R. A.; Larionova, J.; Guari, Y. Nanoscale 2023, 15, 144 – 153.

3 In preparation

4 Guselnikova, O.; Trelin, A.; Audran, G.; Joly, J.-P.; Tretyakov, E.; Švorčik, V.; Lyutakov, O.; Marque, S. R. A.; Postnikov, P. Chem. Sci. 2021, 12, 4154-4161.

Séminaire organisé dans le cadre du programme interdisciplinaire MAT-PULSE