Design,Synthesis And Study Photovoltaic Properties Of Highly Efficient And PH Neutral Conjugated Polyelectrolyte Anode Modified Layer Materials

Organic solar cells as a new generation large photovoltaic device that has low cost,lightweight and flexible.It can be widely used in portable electronic products,smart devices,etc.electrode modified layer and intermediate layer connection interface materials as a key component of OSCs,it has fine control between electrode and active layer energy level,adjust the built-in electric field,determining electrode polarity and enhance the capacity of charge collection,control surface energy to regulation active layer morphology,control the light field in the active layer that enhance the active layer for light utilization factor,improveing active layer with electrode of interface stability and function.Therefore,the interface modification layer materials play an important role in improving the efficiency and stability of OSCs.Currently widely used PEDOT:PSS of hole transport layer has disadvantages such as low conductivity,acid and moisture absorption,but conjugated polyelectrolyte polymer(CPE)has π conjugated main backbone,the side chain has ionic functional groups and a good link is established between the hydrophilic electrode and hydrophobic active layer.Otherwise CPE shown as the unique advantages of interface layer material,and can be simply by changing the composition of the main chain or side chain,to realize the optical properties,electrical properties,aggregation morphology and properties of the solution of control.In this paper,synthesis of several p-type conjugated self-doping polymers,as a hole transport layer used in OSCs self-assembly device,to studying the hole transport layer is how to optimize the photovoltaic performance of the device,and for the sake of optimize the structure of CPE material.Base on 4H-Cyclopenta[2,1-b:3,4-b’]dithiophene,thiophene and 2,2’-thiophene units,by Suzuki coupling reaction to synthesize two kinds of p-type conjugated self-doping polymers name as PCPDT-T and PCPDT-2T,base on active layer of PTB7-Th:PC71BM,the PCPDT-T exhibits higher,more homogeneous conductivity and appropriate work function,which make it as ideal HTL materials for OSCs.The single-junction OSCs modified with PCPDT-T HTL showed an outstanding power conversion efficiencies of 9.3%,which is much higher than that of the PEDOT:PSS modified devices(8.0%).Because PCPDT-2T has not been good in modifying the work function of electrode material that the PCPDT-2T modified device(7.6%).Notably,PCPDT-T HTL exhibits excellent thickness-insensitivity in fabricating OSCs devices.The OSCs devices with very thick PCPDT-T interlayers over 50 nm still demonstrated power conversion efficiencies over 7.1%,PCPDT-T shows excellent interface modification,as well as very compatible to meet the requirement for future roll-to-roll printing.The work function of PCPDT-T is lower than that of PEDOT:PSS affects the improvement of OSCs Photovoltaic performance,in order to design more reasonable work function of the CPE interface layer material,based on carbazole,benzene and2,1,3-Benzothiadiazole synthesis PCB-BT and PCB-Ph.Using PBDB-T:ITIC as active layer for OSCs,due to the PCB-BT has a more reasonable work function compared with PCPDT-T,and isotropic conductive ability,PCB-BT as hole transport layer device energy conversion efficiency reached 10.07%,than PCPDT-T device(PCE=9.19%)increased by 0.92%,and the PCB-Ph conductivity below PCPDT-T and PCB-BT,so that the hole transport layer for PCB-Ph device PCE of 8.25%.