Research On High Performance Perovskite Solar Cell With Polymer Acceptor Layer

Perovskite materials have attracted much attention due to their strong light absorption capacity,high carrier mobility,easy regulation of bandgap,long carrier life,and multiple processing modes.After just ten years of development,the photoelectric conversion efficiency of perovskite solar cell has increased from 3.81% to 25.2%.Among them,perovskite solar cells with flip-side planar heterojunction structure have become one of the mainstream research directions due to their simple preparation process and excellent photoelectric.In the current research of flip-chip planar heterojunction perovskite solar cells,fullerene and its derivatives are the most commonly used acceptor materials,but this material is easy to aggregate,unstable and relatively expensive to produce;while polymerization acceptor materials have the advantages of better film-forming ability,low production cost,easy energy level control,and good hydrophobicity to ensure the long-term stability of the device,which have attracted widespread attention from relevant researchers.Therefore,in this paper,two new types of polymer acceptor materials were used as the acceptor layer to prepare high-performance perovskite cells.Subsequently,the surface of the perovskite active layer film was modified with interface modification materials,which improved the device performance,and the mechanism of performance improvement was studied.Firstly,the optimal solution concentration and film-forming process of the polymer acceptor material were explored.After optimizing the polymer ZLP12,polymer ZLP26 material film and the prepared device,it was found that the optimal solution concentration is 2 mg/m L,the optimal speed is 3500 rpm,the prepared acceptor film has small roughness,high coverage,few defects,and suitable thickness.And the photoelectric conversion efficiency of the corresponding device can reach up to 11.28%,but it has a certain hysteresis effect.In order to further improve the photoelectric performance of the devices of ZLP12 and ZLP26 acceptor layers,polymethyl methacrylate(PMMA)was introduced to modify the surface of the perovskite active layer film.The photoelectric conversion efficiency of the device is increased to 12.85%,and the device’s hysteresis effect has also been improved,mainly due to the passivation of PMMA on the surface of the perovskite film,which enhances the interface contact between the acceptor layer and the perovskite layer,reduces the carrier non-radiative recombination channels,and improves the device photoelectric performance.After in-depth research and analysis of the above experimental results,I tried to mix PMMA directly into the PCBM solution and configure it as a PMMA: PCBM blend solution,spin-coated into a film directly as the acceptor layer of the perovskite solar cell.By optimizing the process,a high-performance perovskite solar cell was obtained.The photoelectric conversion efficiency of the device can be as high as 17.72%,and the initial photoelectric conversion efficiency can still be maintained above 80% after being left in the environment for 30 days.Compared with the device with PCBM acceptor layer,the photoelectric performance and stability of the device with PMMA: PCBM acceptor layer have been greatly improved.