Mesoscopic perovskite solar cell
"A mesoscopic PSC is generally composed of dense anatase TiO2 and mesoscopic anatase TiO2 nanoparticles (NPs), which are crystallized by high-temperature processing at over 450 °C. Such high temperature improves the crystallinity and forms necking among each NP, which improves the electron-transport properties of the film. It was recently reported that lithium-doped mesoscopic TiO2, in the form of lithium carbonate, can further improve the electrical properties of mesoporous TiO2, which can result in high current density of over 26 mA/cm2, thereby achieving device efficiency exceeding 25%.34 However, the mesoscopic TiO2 structure remains problematic for large-scale production."
The TiO2 possesses oxygen vacancy or surface defect. Under bias voltage this Oxygen vacancy can migrate. The accumulation at TiO2/perovskite interface hinder the electron extraction. It causes hysteresis which can be used as Memristor
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