MOPTOPus · Metal oxide nanocrystals as optically driven dynamic manipulators of local (opto)electronic properties

Metal oxide nanocrystals as optically driven dynamic manipulators of local (opto)electronic properties

Nanoscale structuring can add exciting new functionality to materials altering their way of interacting with light. This might be beneficially exploited for light harvesting systems in energy applications, such as photovoltaics, but also for solid state lighting and new technologies such as quantum information. For example certain materials show enhanced light absorption and emission when structuring them as monolayers, with respect to their bulk counterpart. These so called two dimensional layered materials are only several atoms thick, which corresponds to a few tenth of a billionth of a meter, while their lateral dimensions can extend to several micrometers. This restricts the motion of their electrons to the two-dimensional plane, while the third direction is governed by quantum mechanics, largely influencing their electronic structure. Due to the small size of the active material, the physical and electrical connection of such nanoscale functional material to devices of dimensions several orders of magnitude larger, as used in our daily lives, impacts the nanomaterials' structural and optoelectronic properties. Within this project we aimed to establish a contactless approach to their manipulation controlled entirely by light. The exploitation of such a contactless approach is fundamentally new and allows accessing and dynamically controlling material properties at nanometer length scales previously hampered due to their connection to bulky devices. To this aim we interface the layered two dimensional materials with small semiconductor crystallites of several nanometers only. Such materials are grown bottom up in solution and stabilized to form floating nanocrystals and serve as light-driven charge injection sources. This light-triggered and contactless hybrid nano-device enabled us to very locally manipulate the layered two dimensional materials in the nanometer range, of enormous importance for quantum optics application. Finally, the results of this project lead to the development of novel nanocapacitors that are charged only by light, hence taking a step towards the direct light energy storage. This is a first step towards the development of storage devices that are charged up directly by the sun and of fundamental importance for the development of green and sustainable energies. All together the outcome of this project has allowed me to receive the ERC Starting Grant 2019 and ultimately a Tenure Track Researcher position at the Italian Institute of Technology, Genova, Italy.

Data: CORDIS, © European Union