Preparation And Research Of High-efficiency Carbon-based Perovskite Solar Cells

In recently 10 years,the certification efficiency of perovskite solar cells has rapidly developed to 25.5%,which is a promising clean energy.The stability problem that limits its market development has also been improved.which makes perovskite solar cells attract much attention.In perovskite solar cells,the interface morphology and electron/hole transport process are the main factors that affect the performance of devices,and they are one of important topics to enhance the photoelectric property and stability of devices.In this paper,carbon electrode is used to replace the traditional metal electrode to save the manufacturing cost of the device.The inorganic CsPbIBr₂ perovskite with appropriate band gap and excellent thermal stability is selected as the light absorbing layer to regulate the interface contact and hole transport on the anode side of the device(1)By introducing PbI₂ into the precursor solution of CsPbIBr₂,the properties of CsPbIBr₂ thin films and devices with different concentrations of PbI₂ were analyzed.After adding PbI₂,large grain CsPbIBr₂ thin films with high density,no holes and full coverage were obtained,which enhanced the light absorption ability of the films.With less Eloss,less internal defects,higher internal resistance,less non radiative recombination and higher efficiency perovskite devices were obtained.The HTL free carbon based CsPbIBr₂ solar cells obtained 8.81%PCE and 1.24 V Voc.(2)Based on the above work,we add the material that carries the holes,P3HT.It was found that the polar solvent dissolving P3HT would not destroy the perovskite crystal,P3HT would increase the hole extraction ability and carrier transport performance between the perovskite film and the carbon electrode.Then we optimizes the speed of the P3HT spin coating,when 3000 revolutions per minute,the thickness of the P3HT is optimal.After assembled,,the PSCs of carbon based CsPbIBr₂ reached 9.46%PCE and 1.26 V Voc.