Preparation Of Perovskite Materials And Related Properties

Perovskite is a kind of materials with the same crystal structure of calcium titanate(CaTiO3),which was discovered in 1839.Two-dimensional organic-inorganic hybrid perovskite material was considered as a new and promising optical material which entered into people's view in 2009.This kind of perovskite material has great potential applications in the field of solar cells.The main contents of this paper are listed as follows:1.This experiment synthesized a two-dimensional organic-inorganic perovskite of the type NH3(CH2)10NH3)PbBr4 by reprecipitation method.The obtained powder can emit fluorescence at 550 nm when excited at 270 nm in the mixture of DMSO/H2O>4/6.When Hg2+ and rhodamine ethylenediamine(RhHB)are added into the solution,the ring opened with fluorescence response.As the concentration of Hg2+increased,the intensity of the corresponding RhHB-Hg2+ at 585 nm was gradually increased,and the intensity of the corresponding C10PbBrPE at 550 nm was gradually reduced.The test showed that the emission peak of the perovskite overlaps the 585 nm absorption of rhodamine B,and Forster distance was calculated as 10.37 A.The FERT system can be used to detect Hg2+,with a detection limit of 2.4 p,M.2.Then CH3NH3PbBr3quantum dots(MAPB)were synthesized by coprecipitation method.In order to improve the stability of MAPB,we hope to prepare a substance with MAPB to form complex to protect MAPB.We choose gels as protective substance because the gel factors can form a stable three-dimensional network structure by interacting with each other by non covalent bonds.So,the gel factor based on sorbitol was prepared and the most suitable conditions for the formation of complex between MAPB and gel were investigated.The tests showed that organogels can form organogels by self-assembly,and the MAPB quantum dots are wrapped up to form a complex MAPB-G3.The fluorescence stability of MAPB quantum dots and MAPB-G3 was comp,ared.The test results show that MAPB-G3 can improve the stability of MAPB quantum dots compared with pure MAPB quantum dots.3.The previous studies have showed when the relative temperature higher than 50%,the perovskite cell film devices will decompose.In order to improve the stability of perovskite cell,we use MAPB and MAPB-G3 as the perovskite light absorbing layer by spin coating method to prepared perovskite solar cell,respectively.The structure of perovskite solar cells were ITO/Carbon powder/ZnO/perovskite light absorbing layer/PEDOT-PSSNa/ITO.Moreover,J-V curve were tested,the result showed that when the humidity was 60%,the conversion efficiency ? of MAPB cells within a week dropped from 0.55%to 0.20%,however MAPB-G3 cells conversion efficiency ? was decreased from 0.54%to 0.22%,which indicated that the MAPB-G3 gel composite was less sensitivity to humidity than MAPB the solar cells.It can effectively improve the stability and it is a positive effect on promoting the development of perovskite cell.