The activities of the Solar Energy Materials and Systems Group (SEMS Group) are centred on the development of new materials and processes for advanced thin film PV technologies compatible with the requirements of sustainability, compatibility with industrial mass-production with very low environmental impact, high efficiency and low manufacturing cost. The SEMS Group is very active in the development of thin film technologies based on inorganic chalcogenide compounds, including technologies that are already at the industrial exploitations stage – as those related to Cu(In,Ga)(S,Se)2 (CIGS)- as well as emerging technologies based on new materials such as kesterite (Cu2ZnSn((S,Se)4 (CZTS)) compounds, and new low dimensional chalcogenides including Sb2Se3. This includes also an intense activity in the research and development of advanced characterization methodologies suitable for quality control and process monitoring applications.
The aim is the exploitation of the technological flexibility of chalcogenide based technologies for the development of device and process concepts suitable for next generation PV integrated components and systems, looking for an ubiquitous penetration of PV in all scenarios of human activity. This includes low weight flexible devices for light weight solar roofs, ceramic-based solar tiles for building integration, semi-transparent devices for glass based façades and solar windows, as well as solar harvesting devices for IoT applications.
Main research lines active in the group are:
• Development of new materials and device concepts for advanced cost-efficient PV: Kesterites, wide band-gap chalcogenides, alternative thin film PV semiconductors, bifacial cells, semi-transparent devices, multijunction concepts, alternative flexible / light weight / ceramic substrates;
• Low cost industrial compatible processes for sustainable high efficiency chalcogenide based technologies: Sequential process (sputtering), Electrodeposition, spray pyrolysis, chemical bath deposition, printing;
• Advanced characterization methodologies in thin film PV technologies: Development of techniques suitable for Quality Control & Process Monitoring (multi-wavelength resonant excitation Raman scattering, elastic light scattering, PL…)