Researchers from the University of Cambridge, in collaboration with Cambridge's Cavendish Laboratory, the Diamond Light Source synchrotron facility in Didcot and the Okinawa Institute of Science and Technology in Japan, have used a suite of correlative, multimodal microscopy methods to visualize, for the first time, why perovskite materials are seemingly so tolerant of defects in their structure.
The impressive performance of perovskites is surprising, as the typical model for an excellent semiconductor is a very ordered structure, but the array of different chemical elements combined in perovskites creates a much 'messier' landscape. This heterogeneity causes defects in the material that lead to nanoscale 'traps', which reduce the photovoltaic performance of the devices. But despite the presence of these defects, perovskite materials still show efficiency levels comparable to their silicon alternatives. In fact, earlier research by the same group has shown the disordered structure can actually increase the performance of perovskite optoelectronics, and their latest work seeks to explain why.