From Space to Earth: Nanotechnologies for the Photovoltaics of Tomorrow

This research illustrates the transition of high-efficiency photovoltaics from space applications to terrestrial use to meet global energy demands. As current silicon technologies have reached their physical limits, researchers are focusing on developing third-generation solar cells. The Physics and Semiconductor Technology (FTS) group at the University of Salento’s Department of Innovation Engineering is spearheading this innovation by using nanostructured materials—such as nanowires and graphene—to maximize light absorption while reducing costs. Through advanced deposition techniques, the study explores the synthesis of innovative semiconductors and functional oxides in collaboration with ENEA. These breakthroughs not only enhance solar energy capabilities but also find applications in water splittingand various cutting-edge optoelectronic devices. The ultimate goal remains achieving the sustainable development targets set by the United Nations for 2030.

To achieve these goals, photovoltaic solar systems represent one of the most concrete solutions for meeting the growing global demand for energy and mitigating environmental impacts. However, the solar technologies currently in use on our planet are reaching their theoretical and practical limits. The current terrestrial photovoltaic market is dominated almost entirely by silicon solar cells. These traditional cells exhibit a solar-to-electricity conversion efficiency (PCE) that does not exceed 25%. Further efficiency gains for this class of devices are severely hindered by technological constraints and fundamental physical mechanisms. To overcome the limitations of conventional technologies, the research frontier is focusing on third-generation photovoltaics, based on the use of nanostructured solar cells. By utilizing small volumes of nanocrystalline semiconductor materials, it is possible to activate entirely new and more efficient physical mechanisms for absorbing sunlight and converting it into electrical energy, while simultaneously reducing production costs. The FTS group within the Department of Innovation Engineering is active in this advanced field, with the primary objective of developing high-efficiency, low-cost nanocrystalline solar cells.

However, the SPT group's nanotechnology research extends beyond direct solar energy. In collaboration with the ENEA Research Center in Brindisi, nanostructured functional oxides are being synthesized. These advanced materials find application in various strategic areas for the energy transition and future technologies: next-generation photovoltaics; water splitting for clean hydrogen production and photocatalysis; and advanced optoelectronic, electromagnetic, thermoelectric, and sensing systems.