Abstract
Chemical technologies based on light have acquired a paramount importance in the last years, as they can allow the realization of sustainable systems for the production of energy and heat and for the fuelling of chemical transformations, as well as the remote control of chemical switches and material response. Among the different applications, photothermal catalysis (PTC) is of particular relevance since it allows to use low intensity irradiation, as that provided by solar light, to promote the conversion of raw materials, including environmentally dangerous chemicals, into useful products, as fuels. Nanosized photothermal agent (nPTAs), i.e. nanostrucuterd materials capable to convert the energy associated to light into chemically exploitable forms, are the crucial elements of PCT. Photothermal catalysis is thought to proceed mainly by nPTAs-induced generation and injection hot-electrons, in combination with other photochemical effects. However, we are convinced that also the specific temperature enhancement achieved in the close proximity of the nPTAs can play a relevant role. Unfortunately, the investigation and development of applications of the photothermal effect is hampered by the fact that the few physical methods available to detect local temperature changes at the nanometer scale present several drawbacks, including the need of intense focalized laser irradiation and of expensive and dedicated custom setup, and in particular the lack of sufficient spatial resolution. On the other hand, fluorescence based molecular thermometers are not sensitive enough to allow the investigation of small samples fractions and can be hardly applied to systems featuring relevant quenching ability. In this project, we propose to solve this problem by developing tools capable to amplify the response by “integrating” in time the effect of the localized photoactivity. This goal will be achieved using irreversible OFF/ON probes based on photolabile linkers. The switching on of these probes will be hence the demonstration that high temperature has been reached at least in proximity of the nPTAs. The amount and localization of the products will provide information about the temperature reached and the size of the photoactive area. Three different classes of nPTAs, granting the appropriate features to effectively promote PTC will be studied, namely gold plasmonic nanoparticles, graphene derivatives and melanin-like nanoparticles. The application of our newly developed probes to these nPTAs will bring about several relevant achievements: namely, the understanding of the heat generation effect by nPTAs at the nanometre scale, a detailed comprehension of the mechanisms of photothermal catalysis, the proof-of-concept demonstration of the possibility to use localized photoinduced heating to promote chemical reactions, the development of thermolabile linkers that could find applications in fields as drug release and phototriggered materials.
Dettagli del progetto
Responsabile scientifico: Marco Montalti
Strutture Unibo coinvolte:
Dipartimento di Chimica "Giacomo Ciamician"
Coordinatore:
Università degli Studi di GENOVA(Italy)
Contributo totale Unibo: Euro (EUR) 112.000,00
Durata del progetto in mesi: 24
Data di inizio
30/11/2023
Data di fine:
28/02/2026
