Synthesis And Performance Research Of Organic Photovoltaic Materials Based On Porphyrins

Porphyrin-based compounds or polymers have become dye sensitizers and active layer materials of novel solar cells because of porphyrin compounds possess high molar absorption coefficient,high thermal stability,excellent electrochemical performance and electron transport capability and other features.This paper reviews the research progress of porphyrin derivatives in bulk heterojunction solar cells(BHJ SCs)and dye-sensitized solar cells(DSSCs),and related design strategies of porphyrin derivatives as dye sensitizers and active layer materials.By considering the absorption spectra,molecular energy levels,solubility properties,electron/hole mobility,and phase morphology etc,four polymer donor materials based on porphyrin unit and two dye molecules based on triphenylamine derivatives and porphyrin were designed.The intermediates and target molecules were characterized by using the NMR spectra,MALDI-TOF MS and elemental analysis etc test means.The main research contents were listed below.(1)Four copolymers(XP10,XP11,XP12 and XP13)based on diketopyrrolopyrrole(DPP)and carbazole units with tetrathiophene porphyrin(TTP)side chains linked by a flexible alkyl-interval were designed and synthesized.The effects of the introduction of TTP on the optical and electrochemical properties,the morphology,the mobility and the photovoltaic performance of copolymers were systematically studied.The research results revealed that XP11 with a TTP/DPP ratio of 2/8 possessed the best performances,containing broad absorption spectra,balanced hole/electron mobility and suitable microphase separation.After optimizing via solution vapor annealing,the organic solar cell devices based on XP11 and PC71BM showed the best power conversion efficiency(PCE)of 5.11%with a short-circuit current density(Jsc)of 10.36 mA cm-2,an open-circuit voltage(Voc)of 0.77 V,and a fill factor(FF)of 0.64.(2)Two dye molecules(XDBT and XDffBT)based on triphenylamine derivatives,porphyrin units and benzothiadiazole units(BT)were designed and synthesized.The effects of the introduction of F atom on BT on the photophysical properties,electrochemical performance,adsorption capacity,impedance and photovoltaic performance of the dyes were studied.The research results showed that the dyes of containing F atoms on BT obtained a high molar absorption coefficient,a high open-circuit voltage,a little adsorption amount and a strong aggregation phenomenon.After adding 1 mM CDCA,XDBT obtained PCE of 5.24%,and XDffBT obtained PCE of 4.17%.