Highly efficient bifacial semitransparent perovskite solar cells based on molecular doping of CuSCN hole transport layer |
(a) Valance band spectra of the CuSCN and F4TCNQ-doped CuSCN. (b) UPS spectra of the CuSCN and F4TCNQ-doped CuSCN, measured under −21.22-eV bias. Band bending at CuSCN-perovskite interface of before (c) and after (d) doping F4TCNQ. |