| Based on the background of energy crisis,the research and development of photovoltaic devices is imminent.Traditional monocrystalline silicon solar cells are not ideal photovoltaic devices due to their high cost,numerous preparation processes,strict technological requirements and serious waste water pollution in the production process.The new thin film solar cells are represented by perovskite solar cells,which have low cost,simple structure,low preparation process requirements,good transmission efficiency,carrier bidirectional transmission characteristics,etc.,and gradually show its uniqueness and competitiveness,and have commercial potential.This paper mainly adopts the interface optimization strategy to optimize and regulate the interface of the electronic transport layer/perovskite light absorber of perovskite solar cell devices,and adopts A-doped to regulate the crystal structure of perovskite light absorption layer,so as to improve the photoelectric conversion efficiency of perovskite solar cells as A whole.The main research contents and results are as follows:（1）Based on the interface optimization strategy of PSCs,PbS-QDs was introduced into the interface of ETL/MAPbI3 layer to assemble PSCsdevices.PbS-QDs was introduced on the surface of Ti O2 electron transport layer by in situ growth method,and the content of PbS-QDs on the surface of Ti O2 mesoporous layer was controlled by impregnation period.PbS-QDs was used to modify the ETL/MAPbI3layer interface of PSCs,and combined with the concentration of MAPbI3 precursor solution,the photoelectric conversion performance of PSCsdevices was co-optimized.PbS-QDs can adjust the energy level band gap of Ti O2 mesoporous layer and participate in the reaction of MAPbI3 layer to a certain extent,resulting in residue of PbI2 impurity phase in MAPbI3 layer.With the increase of PbS-QDs content,the open circuit voltage of PSCsincreased gradually.When the PbS-QDs impregnation cycle was 3 times and the concentration of MAPbI3 precursor was 1.5 M,the photoelectric conversion efficiency of PSCswas optimal.Although the introduction of PbS-QDs will sacrifice a part of the short-circuit current of PSCsdevices,overall,the photoelectric conversion efficiency of PSCsdevices is increased,and the final photoelectric conversion efficiency of 12.98%is obtained（2）.Based on the A-site doping MAPbI3 layer strategy,Csdoping MAPbI3 layer was used to assemble the PbS-QDs/Ti O2 based PSCsdevice.Cs-doped MAPbI3 layers were prepared by one-step solution deposition with different concentrations of Csdoped MAPbI3 precursor solution.The crystal structure of perovskite absorption layer was regulated by smaller inorganic cations to improve the tolerance factor of perovskite.Combined with the interface optimization strategy in（1）,PbS-QDs/Ti O2based Csdoped MAPbI3 perovskite solar cells were assembled.The experiment proved that the introduction of Cs+could reduce the internal defects of MAPbI3 layer and increase the optical stability of PSCsin the photoelectric transmission process.With the increase of Cs+content in the system,the short-circuit current firstly increases and then decreases.When the Cs+content reaches 3%,the photoelectric conversion efficiency of the assembled PSCsreaches the optimal value,which is 13.15%... |
