Inspired by nature, capture and conversion of solar energy in a chemical product for energy storage and conversion is studied in artificial photosynthesis. While in biological systems catalytic processes are accomplished by proteins, in artificial photosynthesis inorganic catalysts transform target molecules into solar fuels. A model case is the process of water splitting, where photo-catalysts are employed to convert the energy of sunlight into H2, which can be used as combustible in a proton exchange fuel cell by the use of Pt-based catalysts. There is a long path to walk for the implementation of these technologies; limitations exist for the efficiency, stability and cost of both photocatalysts and Pt-based catalysts.
It is believed these challenges can be addressed at the nanoscale by enhancing the efficiency of catalysis due to the high aspect-to-surface ratio and tailor-making material platforms based on colloidal nanocrystals (NCs) with uniform size and well-defined morphology. Parameters which define the optimized performance of a catalyst strongly depend on the atomic distribution and organization in the material since the characteristic length and time scale of charge carriers in a photocatalytic reaction naturally falls into the nanoscale, this is why well defined, scalable and safe NCs need to be produced for a correct targeting of the reactions.
In this context, the aim of the project is to obtain novel catalytic complex materials by designing, producing and unveiling general trends in the colloidal production of advanced multifunctional NCs. Two types of catalysts will be explored: i) semiconductor-based NCs for the efficient transformation of solar energy to solar fuels and ii) Pt-based NCs for the low-cost transformation of solar fuels to electrical energy.
Although focused on water splitting, this research pretends to be a tool box for providing materials and synthetic strategies for the production of solar fuels. In this regard, NCs production will be carried out from an integral perspective, including feasibility, nanosafety and sustainability from the earlier steps of design.