Organic-inorganic Hybrid Thin Film Of PEDOT/V₂O₅ As Anode Buffer Layer In P₃HT/PC₆₁BM Hetero-junction Polymer Solar Cells

Polymer solar cells have become a research hotspot because of their light weight,flexible devices and easy preparation for large-area.The interface buffer layer matches and adjusts the work function of the two layers,and it not only reduces the series resistance of the whole device,but also improves the collection efficiency of electrons or holes.The interface buffer layer material selectively transports carriers,which can reduce the recombination of electrons and holes.Therefore,the selection of a suitable interface buffer layer material is of great significance for improving device performance.Based on the structure of ITO/PEDOT:PSS/P3HT:PC₆₁BM/Al,the preparation process of vapor-deposited Ca electron transport layer was explored.On this basis,PEDOT film and V₂O₅ film were prepared via in-situ synthesis,and the two layers together were used as hole transport layer,and the preparation conditions of PEDOT/V₂O₅ hole transport layer was optimized.Applying it to polymer solar cells,a highly efficient and stable device is obtained,and the PEDOT/V₂O₅ hole transport layer performs better than the PEDOT:PSS hole transport layer.The main contents of this paper are as follows:?1?Exploring the preparation process of Ca electron transport layer in polymer solar cells.The effects of evaporation rate and thickness of Ca electron transport layer were tested.We found that the optimum evaporation rate of Ca electron transport layer was 0.01 nm/s,and the device performance was optimal when the vapor deposition thickness was 10 nm.On this basis,the solvent annealing of active layer was to promote the phase separation of P3HT and PC₆₁BM by solvent evaporation in the active layer.It was found that when the spin coating time was 60s,then annealing at 120 ^oC for 10 minutes,the device performance is optimal.?2?An organic-inorganic hybrid thin film of PEDOT/V₂O₅ complex was successfully obtained via in-situ synthesis method.PEDOT buffer layer was prepared by oxidative polymerization.V₂O₅ nanoparticles were subsequently prepared.A double layer compound anode buffer layer PEDOT/V₂O₅ has been successfully applied to polymer solar cells.According to our optimization processes,the results indicate that power conversion efficiency of ITO/PEDOT/V₂O₅/P3HT/PC₆₁BM/Ca/Al device is achieved 3.76%,which has been improve 8%compared with prototype of P3HT/PC₆₁BM polymer solar cells.Moreover,the air tolerance of the devices is also better than prototype of P3HT/PC₆₁BM polymer solar cells.PEDOT has excellent charge transport performance,V₂O₅ nanoparticles modifies the surface defects of PEDOT,the combination of the two materials makes an anode buffer layer with excellent performance.