Exploring the Recombination Mechanism Induced by Carrier Transport Layers in Perovskite Solar Cells

We present the exploration of characteristic impacts on perovskite solar cells (PSCs) induced by the organic or inorganic HTLs. In this work, the perovskite devices have been fabricated by employing the organic (PEDOT: PSS, PTAA) or inorganic (NiO
_x
, CuI) HTLs and investigated the limitation factors by optoelectronic characterizations. The optoelectronics impacts on the devices were investigated by analyzing the current-voltage characteristics and capacitance spectra. A lower interface activation energy (E
_A
) for PEDOT: PSS device indicates defect mediated recombination at the interface. The inorganic HTL induces rather deep defects than an organic one. This is presumed to be due to the diffusion of metal ions from inorganic HTL to the perovskite film. The recombination mechanism in the device is influenced by the nature of HTL on which perovskite film is grown.