Perovskite solar cells that are carriers of charge can be lost through recombination occurring at interface defect sites. While recombining the defect sites within the perovskite layer limits the performance of the solar cells at present. Teams from the University of Potsdam and the Helmholtz-Zentrum Berlin reached the conclusion through accurate quantitative measurements on 2 perovskite cells which uses photoluminescence.
Even solar cells made from perfect miracle material is not able to convert sunlight to electricity as theoretically calculated maximum achievable power is incomplete without the position of energy bands of electrons and unavoidable radiation of photons. For instance, maximum power conversion is approx. 33 percent, but it will never archive its maximum production values due to defects in the kinds are leading to loss of charge carriers. In order to achieve the maximum values, it is required to detect the defects in solar cells.
At these defects in the crystal lattice in the perovskite layer is charge carriers that have released by sunlight and recombined again and lost. But these defects are within the layer of the layers of perovskites.
This way they were able to calculate losses of cells and thereby determine the most harmful defects present in the perovskite absorber layer and charge the transport layers and withdraw them. With these findings, the group of researchers is led by Dr. Dieter Neher and Dr. Martin Stolterfoht the professors at the University of Potsdam succeeded in the substantial reduction of interfacial recombination and improving the efficiency of solar cells with 20 percent.