Research Focus

Printable solar cells (such as organic photovoltaic cells and perovskite solar cells) are regarded as the next generation photovoltaic technology because of their flexibility, light weight, low cost and many other advantages. Based on soluble semiconductor materials, the technology forms a photoelectric converter device with sandwich structure by printing. Due to the influence of liquid-solid phase transition, solvent, temperature and substrate surface in the printing process, most of the semiconductor films are polycrystalline or even amorphous, and the atoms / molecules lack long-range order, resulting in the low transmission efficiency of carriers in the film. From the device level, there are many heterogeneous interfaces such as electrode / charge transport layer / light absorption layer and even donor / receptor in printable solar cells. The transmembrane transport of carriers is affected by multiple factors such as space distance, energy band structure and interface defects, resulting in serious interface recombination. In addition, for some organic semiconductor materials, due to the lack of rigidity of the conjugated main chain or the influence of the micro chemical environment, the molecules tend to curl in the spatial configuration, can not form a good conductive path, and the carrier transmission resistance is large. Therefore, we will strengthen carrier transport from the three dimensions of film, interface and molecule to realize efficient printable solar cells.