Study On Electrode Modification For Organic Light-Emitting Devices And Organic Photovoltaic Cells

Organic optoelectronic devices have the advantages of heavy mass, thickness, easy preparation, low-cost and flexible, and after decades of development, it has gradually marketized. As an emerging industry, organic photovoltaic devices have broad application prospects, but it wasn’t industrialized and has much room for improvement, for example, metal electrode and the contact interface of organic materials generally have a greater barrier. In this paper, the approach of modifying the electrode to reduce the contact barrier was studied, and the specific work was as follows:Firstly, we processing ITO in electrochemical in which ITO and molybdenum served as electrode, with HCl as the electroilte. Unlike the method of soaking ITO with acid solution, positive and negative ions will drift directional under the action of electric field in electrochemical treatment. The transmittance in the NIR region had increased after the electrochemical treatment. Among the OLED fabricated on treated ITO, the device treated had lower open voltage at-1V, luminance of50000cd/m2and power efficiency681m/w, increased47.2%.Secondly, we studied the devices fabricated in pentacene, a P-type material, and ITO was served as cathode. Here, pentacene was in action of electron injection layer. We fabricated organic solar cells with inversion structure, ITO/pentacene(Xnm)/Cs2CO3(2.5nm)/BCP (7nm)/C6o(40nm)/CuPc(20nm)/MoO3(10nm)/Al(150nm) with various thickness of pentacene.The best device got short current as2.62mA/cm2, efficiency over0.364%, and open voltage over0.526V, efficiency and open respectively increased18.6%and8.5%.At last, we investigated the organic solar cells in inversion structure that use Al which was modified by ammonium hydroxide with electrochemical treatment as the cathode modification layer. At first, we had made device with ITO that deposited different thickness Al. It proved that when Al was in2nm that the efficiency was optimal. Then, we use electrochemical method processing2nm Al on ITO in different times by NH3H2O dilute. The OPV made of these cathode showed that when the thickness of Al was2nm and the processing times was40s, the improvement of the device was the best, the filling factor was above54.6%, increased5.2%and the efficiency was0.456%, increased29.2%.