Enhancing current density of perovskite solar cells using TiO2-ZrO2 composite scaffold layer

A novel scaffold layer composed of TiO2-ZrO2 composite was fabricated for perovskite solar cell. Compared with pure TiO2 nanoparticles (NPs), the relatively larger ZrO2 NPs could increase film roughness and enhance light-scattering effect in TiO2-ZrO2 composite films. The device exhibited outstanding power conversion efficiency (PCE) of 11.41%. The morphology and aggregation of particles, three-dimensional roughness, as well as the ingredient and micro-structure of FTO/compact TiO2/TiO2-ZrO2 was investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscope (AFM), energy dispersive spectrometer (EDS), and X-ray diffraction (XRD), respectively. Moreover, the optical property of TiO2-ZrO2 films for visible light was characterized by UV-visible absorption spectroscopy (UV-vis), and its influence on quantum yield of the device was further demonstrated by incident photon-to-electron conversion efficiency (IPCE). Owing to the inert oxide, the short-circuit current density of perovskite solar cell using TiO2-ZrO2 composition as scaffold layer increased by 21% compared to the one employing pure TiO2 mesoporous film.