Study Of Bimetallic Oxides As Interface Layer Of Organic Solar Cells

For the past few years,owing to the serious environmental pollution,clean energy consumption continues to grow and developing new energy has become the important subject of contemporary science.Organic solar cells?OSCs?has attracted considerable attention from researchers due to their intrinsic advantages,such as simple preparation process,environment friendly and low cost.In recent years,the performance of solar cells has a great improvement,energy conversion efficiency of OSCs have already broken through 11%.As an important part of OSCs,interface modification layer can promote the transfer of electrons and holes and effectively improve the performance of the device.This paper is focused on the composite metal oxides and studied the vanadium bronze which is used as the cathode interface material and cobalt acid nickel which is used as anode interface material,respectively.The main research content of this paper are as follows:1.Optimize the fabricated process of the OSCs used poly?3-hexylthiophene??P3HT?as donor and fullerene derivative as acceptor.By changing the proportion to the donor/acceptor,solvent,concentration of solution,annealing temperature,additives and other factors,the best fabricated conditions of OSCs are achieved.2.Vanadium bronze have been synthesized via vanadium pentoxide and lithium nitrate as the raw material.As the cathode interface material for OSCs,the optimizing device was fabricated by changing the rate of charge synthesis vanadium bronze which embedded different lithium,and then control the evaporation rate and the time to adjust the thickness of the vanadium bronze.The devices were used P3HT and fullerene derivative as the active layer and molybdenum trioxide as anode interface material in this experiment.The results showed that device performance was the best when the number of lithium was 0.5 that embedded in vanadium bronze,meanwhile the deposition thickness of material is 11 nm and the energy conversion efficiency is3.39%.We use vanadium bronze Li_0.5V₂O₅ as interlayer applied in reverse structure solar cells,which showed better performance than the forward structure solar cell.The short circuit current was 9.62 mA.cm-2,and the PCE of reverse structure device was 3.75%.It is commonly recognized that vanadium bronze has appropriate energylevel as the cathode modified layer.Electronic transmission is effectively and the short-circuit current of the device and the energy conversion efficiency is improved.3.Cobalt acid nickel has been synthesized via cobalt nitrate and nickel nitrate as the raw material,which is used as the anode interface material for OSCs.When the concentration of cobalt acid nickel solution is 3 mg/mL,rotating speed is 2000 rpm,cobalt acid nickel can form thin film by spin coating and the performance of the OSCs device achieve the best with the energy conversion efficiency of 3.44%.Cobalt acid nickel has a good permeability for light absorption,good hole mobility and the appropriate energy level as anode layer.All of these factors will contribute to improve the packing factor and energy conversion efficiency of the device.