Interfacial Modification And Device Preparation Of Perovskite Solar Cell Based On Hydrophobic Hole Transport Layer

In recent years,Organic-inorganic hybrid metal halide perovskite materials have been favored in the field of photovoltaic research due to their flexible and adjustable band gap,large optical absorption coefficient,high carrier mobility and long diffusion coefficient.The inverted structure devices?p-i-n?of perovskite solar cells?PSC?has negligible hysteresis effect,full low temperature processing and simple preparation process,high PCE comparable to those of normal structure devices?n-i-p?,which has attracted tremendous research effect.Currently,the most used of hole transport layer material in the inverted structure device is conjugated conductive polymer,whereas most conjugated polymer films are hydrophobic.Although the hydrophobic hole transport layer material has the advantage of insulating water vapor into the perovskite layer,it is also disadvantageous for the deposition of the perovskite precursor solution,which may result in poor coverage of the perovskite film,thereby affecting the performance of the device.In this thesis,a new strategy of pure physical to improve the surface wettability of hydrophobic hole transport layer is proposed.which not only improves the wettability of the surface,facilitates the deposition of the perovskite precursor solution,but also obtains a high quality,fully covered perovskite film.Subsequently,the triple-cation perovskite system based on inverted structure device was further studied,using a novel hole transport layer material Poly[?9,9-di-n-octyldecyl-2,7-diyl?-alt-?4,4'-?N-?4-n-butyl?phenyl?-dipheny-lamine?]?TFB?prepared a high performance p-i-n perovskite solar cell.The major research work of this paper includes the following aspects:1.Using hydrophobic photoelectric conjugated polymer Poly[bis?4-phenyl??2,4,6-trimethylphenyl?amine]?PTAA?,Poly[bis?4-phenyl??4?-butylphenyl)am-ine]?Poly-TPD?,Poly?3-hexylthiophene-2,5-diyl??P3HT?as a hole transport layer material.A layer of low-temperature annealing?120°C?alumina nanoparticle?Al₂O₃?interface is spin-coated thereon,and the wettability of the hydrophobic hole transport layer is improved by this method,so that the perovskite precursor solution can be spin-coated easily.The interface does not affect the optoelectronic performance of the device.At the same time,we not only optimized the spin-coating process and parameters of Al₂O₃at the interface and determined the optimum concentration,but also studied the influence of Al₂O₃ modified hydrophobic hole transport layer material interface on the photoelectric performance of the device.Based on PTAA,Poly-TPD and P3HT as hole transporting layers,the triple-cation perovskite solar cell devices prepared by Al₂O₃had modified interface achieved the highest PCE of 17.41%,16.24%and 15.77%.2.Based on the cell structure of modified by the interface of the hydrophobic hole transport layer,we used a new hydrophobic hole transport layer material TFB,and prepared a triple-cation perovskite solar device based on TFB as a hole transport layer.In this experiment,we investigated the effect of Cs ion addition and halogen ratio on the morphology,structure and cell performance of perovskite crystals in the formulation of triple-cation perovskite precursor solution;a process for preparing a titanium ore film;,comparing the performance of TFB and PTAA as hole transport layer materials in perovskite solar cells,TFB based triple-cation perovskite inverted structure solar cell's open circuit voltage(V_OC)>1.1 V,power conversion efficiency nearly 18%.