CBE Research Report Spring 2017 | Page 31

Student Poster Presentation #21 (Session 2) A Solution-Processed Organometal Halide Perovskite Hole Transport Layer for Highly Efficient Organic Light-Emitting Diodes Yu Tian 1 , Biwu Ma 1,2,3 1 2 Materials Science Program, Florida State University, Tallahassee, FL 32306, USA Department of Chemical and Biological Engineering, FAMU-FSU College of Engineering, Tallahassee, FL 32310, USA 3 Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, USA Abstract Thin film optoelectronic devices have experienced tremendous development over the last decades. The charge transport layers, i.e., hole transport layer (HTL) and electron transport layer, play critical roles in determining the device performance. We have demonstrated a new type of hole transport layer based on organometal halide perovskite CH3NH3PbCl3 for efficient OLEDs. The solvent passivation approach allowed for the formation of smooth neat perovskite thin films with great surface coverage. Solution processed multilayer green phosphorescent OLEDs based on this new perovskite HTL showed superior performance over the device using conventional PEDOT:PSS HTL, with lower turn on and operating voltages, as well as higher luminescence, EQE, power efficiency and luminous efficiency. The improved device performance is primarily attributed to the wide band gap of CH3NH3PbCl3 , suitable energy levels, and efficient hole injection and transport from ITO to CH3NH3PbCl 3 and light emitting layer. Our work demonstrates a new pathway toward highly efficient solution processed multilayer OLEDs, and further establishes organic–inorganic halide perovskites as a new class of semiconductors with highly desirable characteristics for thin film optoelectronic devices. Reference 1. Yu Tian , Yichuan Ling , Yu Shu , Chenkun Zhou , Tiglet Besara , Theo Siegrist ,Hanwei Gao , and Biwu Ma *. 2016. A Solution-Processed Organometal Halide Perovskite Hole Transport Layer for Highly Efficient Organic Light-Emitting Diode, Adv. Electron. Mater. 2, 1600156 30