Synthesis And Optoelectronic Properties Of Conjugated Polymers With Amino Acid Side Chains

In order to alleviate the energy crisis and develop new environmental-friendly energy sources,solar photovoltaic is one of the most effective ways.At present,the photovoltaic industry is dominated by inorganic solar cells,but the problems of complex processes and high costs have not been solved perfectly.The organic-inorganic hybrid solar cell has the advantages of organic materials and inorganic materials,and has been widely studied in the field of photovoltaic cells due to its low temperature preparation and solubilization processing.In particular,organic-inorganic hybrid perovskite solar cells have rapidly become a new star in the field of photovoltaic research due to their rapid breakthrough in photoelectric conversion efficiency.However,due to the large difference in surface polarity between the organic material and the inorganic material,the coupling between the interfaces is poor,which hinders the transfer of carriers at the interface.Therefore,interface modification is critical to optimizing device performance.The organic conjugated polymer material has excellent photoelectric properties,and the compatibility of the organic-inorganic hybrid interface can be improved by introducing functional groups which have specific modification properties in its side chain.In the previous research work of our group,it was found that amino acids have good modification properties for metal oxide semiconductor materials.Therefore,in this paper,we will explore the synthesis of polythiophene derivatives and polyacetylene derivatives with amino acid side chains,improve the contact properties of hybrid interfaces,optimize interface compatibility and the performance of photovoltaic devices.In the synthesis experiment,we explore the synthesis of polythiophene derivatives with amino acid side chains by catalytic oxidative polymerization of anhydrous FeCl₃.The polyacetylene derivative P4 provided by Wuhan University is post-functionalized,and tyrosine is linked on its side.The conjugated polymer P5 is synthesized and its electrochemical band gap is 2.01 eV as measured by cyclic voltammetry.In the application of photovoltaic devices,the conjugated polymer P5 is introduced into a hybrid perovskite CH₃NH₃PbI₃ solar cell.Firstly,we prepare a planar heterojunction device with a flip-chip structure using polymer P5 as a hole transport layer material,and study the interfacial contact properties of polymer P5 with ITO electrode and perovskite film.In addition,in order to study the modification properties of polymer P5 on the perovskite film,the polymer P5 is doped as an interface modified material in the precursor solution of the hybrid perovskite.Perovskite film with micro-spherical morphology is prepared by changing the solvent volume ratio of the precursor solution,and the concentration of the polymer P5 is adjusted to achieve further improvement of the quality of the perovskite film.The photoelectric conversion efficiency of the prepared hybrid perovskite solar cell device is improved from 11.64%to 14.79%.At the same time,the stability of the device is significantly improved,and high performance can be maintained for a longer time in a hot and humid environment.