Preparation And Characterization About ZAO Planar Heterojunction Perovskite Solar Cells

Nowadays,energy consumption is growing and environmental pollution is also increasing.There is an urgent need for all the people to develop new sources of energy.As a new energy source,the cost for manufacturing perovskite solar cells is relatively low and this kind of cells has high photoelectric conversion efficiency,compared with traditional silicon solar cells.So more and more researchers begin to pay attention to this area.But its research is still in the initial stage and there are many problems to solve.For instance,the manufacture technology is not mature and the cells' performance is not stable.Based on this,planar heterojunction perovskite solar cells are studied in the thesis.The content is mainly about the preparation methods of each layer and the test about the cells.In this thesis,ZAO?Zn O:Al?thin films were chosen for the electronic transport layer in the cell.7 groups of ZAO films where the molar concentrations of Al were from 0% to 6% were manufactured by the sol-gel spin-coating technique.Each group of film was uniform and dense with good crystallinity.There were some results observed through the characterization of the films.When A l was doped in ZAO thin films,its crystal structure did not change obviously.The light transmittances of all the ZAO films which had different doping concentrations were good without a great difference and the highest light transmittance in all the films was 87.27%.With the increasement of the doping concentration,the square resistances of the films showed a trend from decline to rise.When the doping concentration was 4%,the square resistance was 22.5 ?/sq.In the ZAO groups,the band gaps had an upward tendency when the doping concentrations increased,and the largest band gap was 3.79 e V.Finally,it is found that the ZAO film whose doping concentration was 4% had the best electron transport capability,so it should be used as the electronic transport layer.For the preparation of perovskite layer in the cell,one-step solution method was adopted and improved.The solvent was the mixure of N,N-Dimethylformamide?DMF?and dimethyl sulfoxide?DMSO?.Lead iodide and ammonium potassium iodide were dissolved respectively.In order to accelerate the solvent evaporation during the perovskite film's forming process,there were some ways adopted in the article: heating substrate before the spin,adding chlorobenzene for the extraction during the spin and blowing the film by nitrogen after the spin.The results were obvious.The films were dark brown,smooth and they had a mirror effect.From the microscopic point of view,the films were uniform with no holes and good crystalline.Spiro-OMe TAD?C81H68N4O8?has a good hole transmission capability and it was chosen for the hole transport layer of the cell using the spin coa ting method.During the assembly work of the cell,ZAO film,perovskite layer,spiro-OMe TAD layer and the gold electrode were on the FTO?SnO₂:F?glass from the bottom up.It could be watched that the electronic transport layer,the perovskite layer and the hole transport layer formed the structure of planar heterojunction.In the end,the battery performance was tested using the standard sun light.It is caculated that the fill factor was 52.6% and the photoelectric conversion efficiency was 6.44%.