Study On Preparations And Properties Of TiO₂ Compact And Composite Mesporous Layers For Perovskite Solar Cells

Recently, Perovskite Solar Cell（PSC） has become a milestone in the development of photovoltaic technology. Compared with the conventional types of solar cells, this new device has more outstanding advantages including simple structure, low production cost and excellent capability of transmitting charge carriers. These unique properties attract public strong interest in the study of this solar cell which makes it a research frontier in this scientific field. A major focus of PSC is the synthesis of CH3NH3PbI3（MAPbI3） and its ramification which functions as light-harvesting and electron-activating material in this cell. On the other hand, the modifications of these organic halide components and improvements of its crystallization are also concerned by scientists.Nevertheless, it is noteworthy that TiO₂ has been still widely applied in PSC as the anode material for its typical characteristic as a stable n-type semiconductor. In most researches, we can discover TiO₂ anode materials play a significant role of restraining the recombination of holes and electrons and provide the passage of charge carriers in the internal circuit. Therefore, adjusting the structure of TiO₂ compact and mesporous layers and improving the contact between TiO₂ and MAPbI3 molecules is an effective method to raise the photoelectric performance of PSC. The main contents and results are summarized as follows:1. TiO₂ compact layers were successfully prepared by spin-coating TiO₂ polymeric pecursor solution. At the same time, the influences of different reaction inhibitors,their diluted concentrations and spin-coating process were investigated in this research. The best 9.34% photoelectric conversion efficiency（PCE） was obtained utilizing C4H11NO2 as the inhibitor under the dilution of 1:1 volume ratio with ethanol,at the spin-coating speed of 5000 r/min for one time.2. TiO₂-ZrO₂ mesporous scaffold layers were synthesized by doping ZrO2nano-particles into 18 NRT agents with polyethylene glycol-400 as dispersant. When doping ZrO2 by the weight of 2.5% TiO₂ 18 NRT, the morphology of this novel composite scaffold layer was remarkably improved. This process also enhanced the performance of PSC at the basis of it whose PCE was 11.4%.3. This research investigated the influences of different reaction inhibitors and their diluted concentrations as well as spin-coating process on photoelectricperformance of the PSC made from them. By means of adjusting the parameters above mentioned, proper TiO₂ compact layers were prepared which effectively promoted the capacity of preventing electron recombination and raised the PCE of this kind of PSC.4. This research adopted relatively inert ZrO2 nano-paticles which covered TiO₂ compact layers to make up the defects on them because of the shortcoming of the spin-coating process. We obtained the excellent photoanode of perovskite solar cells（PSCs） with extremely few energy losses via exploring the optimum proportion of mixture.The photoanodes with new-type structure have provided a new route to enrich the structure diversification of them and improve the light-to-electric energy conversion efficiency of PSC.