Different Side Chain Anchors Zinc Porphyrin Axial Coordination Self-assembled Dye Sensitized Solar Cells

Dye-sensitized solar cells?DSSCs?have become a kind of large-scale production and development potential batteries due to their low production cost,simple synthesis process,simple preparation process,and stable battery performance.In dye-sensitized solar cells?DSSCs?,dye sensitizers are an important component.Among many dye sensitizers,porphyrin sensitizers have a higher molar absorption coefficient,a stronger absorption band in the visible light range,a special macrocyclic conjugate structure,excellent photoelectric properties,and a structure that is easy to modify characteristics and other characteristics have attracted extensive attention and research from researchers.The axial coordination self-assembled supramolecular system of porphyrin also provides a new idea for the design strategy of dye-sensitized solar cells?DSSCs?.Five kinds of anchor zinc porphyrins ZnPAi?i=1-5?with different side chain substituents?p-methylphenyl,p-tert-butylphenyl,2-thienyl,3,5-dimethoxy-4-dodecylphenyl,3,5-dimethoxy-4-hydroxyphenyl?have been designed and synthesized,the structure of the anchored zinc porphyrin was characterized by NMR,mass spectrometry,etc.Assembled it into a dye-sensitized solar cell device,tested its photoelectric properties by UV-visible absorption spectroscopy,and electrochemical impedance,and calculated its stable ground state geometric configuration,front-line molecular orbitals,and electronic transitions using density functional theory to simulate its.The ultraviolet-visible absorption spectrum further elaborates its photoelectric behavior.Then,two types of A4 antenna zinc porphyrins ZnPx?x=1-2??-CF₃,-OCH₃?have been designed and synthesized,and carried out axial coordination self-assembly of the antenna zinc porphyrins and anchor zinc porphyrins.Applied to dye-sensitized solar cells,characterized the molecular structure of the antenna zinc porphyrin by the same method,tested the cell performance,and used quantitative calculation to understand the photoelectric behavior of the assembly.The experimental results show that among the five anchor zinc porphyrins ZnPAi?i=1-5?,the zinc anchor porphyrins containing methyl electron donor groups show better battery performance,especially those with t-butyl structure.Anchor zinc porphyrin ZnPA2 exhibits a high open-circuit voltage of 0.53 V,a short-circuit current density of13.21 mA·cm^-2,a fill factor of 54.29,and a high photoelectric conversion efficiency of 3.85%.When the antenna zinc porphyrin and anchor zinc porphyrin are axially coordinated and self-assembled,the open circuit voltage slightly increases,the short-circuit current density decreases,and the fill factor increases.This is because the energy level of the LUMO orbit of the self-assembly is corrected.The driving force of charge injection is greater,which is conducive to the injection of electrons,which accumulate on the surface of titanium dioxide,resulting in an increase in open circuit voltage.Among the self-assembled supramolecular ZnPx?x=1-2?-ZnPAi?i=1-4?,ZnP1-ZnPA2achieved the highest efficiency of 4.80%,an open-circuit voltage of 0.63 V,and a short-circuit current density of 11.62 mA·cm^-2,filled Factor 65.46.