Crystal Regulation Of Perovskite Films In Mesoscopic Perovskite Solar Cells

Since the beginning of the new era,with the continuous progress of technology,the strategic importance of electronic information materials has become increasingly prominent.As one of the research hotspots of electronic information materials,photovoltaic conversion materials have gradually gained attention,and the increasingly severe energy crisis has further accelerated their development.Perovskite solar cells(PSCs),with their simple preparation process,low production cost,and high-power conversion efficiency(PCE),have emerged as one of the most efficient single-junction solar cells in the field of photovoltaic conversion materials.Printable mesoscopic perovskite solar cells(p-MPSCs)with no hole transport layer are devices prepared using screen printing technology and based on a three-layer mesoporous film framework of mesoporous titanium dioxide/mesoporous zirconium dioxide/mesoporous carbon electrode.Compared to traditional device configurations,pMPSCs have extremely excellent stability and lower production costs,making them the device configuration in the PSCs field closest to commercialization.However,due to the thickness and structure of the mesoporous scaffold in p-MPSCs,the crystallization process of the perovskite is hindered,ultimately resulting in insufficient and non-dense filling of the perovskite film,which is the main reason why the PCE of p-MPSCs is lower than that of planar PSCs.Therefore,regulating the crystallization process of the perovskite film in pMPSCs can help reduce the energy loss inside the device and improve its photoelectric performance.This article mainly focuses on the regulation of perovskite film crystallization in p-MPSCs and aims to improve their performance using additives and solvents.The main research content is as follows:(1)The optimal combination of FA,Cs,and Rb ternary mixed cation-based perovskite as the main precursor is selected,and a ternary mixed solvent system is used for step-bystep annealing.During the annealing process,a culture dish is used to slowly crystallize the perovskite precursor in the mesoporous scaffold under spatial confinement effects,resulting in a more dense filling.At the same time,3-pyridinecarboxamide(NTM)is introduced as an additive to passivate defects in the perovskite film and regulate its work function,reducing the energy loss between the perovskite film and the carbon electrode.(2)2-Methoxyethanol(2ME)is used as the main solvent,and N-methyl-pyrrolidone(NMP)is introduced as a coordinating solvent to prepare MA-based p-MPSCs at room temperature in an air environment.The study explores the advantages of 2ME compared to methylamine-ethanol(MA-Et OH)in room temperature preparation and ultimately forms a continuous and dense film,strengthening the contact between the perovskite film and the three-layer mesoporous scaffold,and improving the short-circuit current and long-term stability.