Enhancing The Efficiency Of Inverted Organic Solar Cells By Using The Exciton Blocking Layers

• Main Authors: Wang, Zhiren, 王志仁
• Other Authors: Meiso Yokoyama
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/70803469603453864167

碩士 === 義守大學 === 電子工程學系 === 100 === In this study, inverted organic solar cells (IOSCs) have been fabricated and characterized. Device’s structure consists of the blend of poly(3-hexythiophene)(P3HT) and [6,6]-phenyl C61-butyric acid methyl ester(PCBM) as an active layer and a solution process WO3 as a hole blocking layer (HBL). The blocking layer possesses high charge mobility and wide band gap. The wide band gap can effectively suppress the diffusion of electron and hole separating from exciton to the electrodes, reducing the combined effect. Experimental results reveal that ZnO annealed in high temperature to procure nano-ridge can effectively enhance holes to transport from active layer to the anode. ZnO is applied in the IOSCs as a HBL to improve the device efficiency. Moreover, WO3 and MoO3 are adopted as the electron blocking layer (EBL) to discuss the impact of energy band diagram and overall surface morphology on the characteristics of IOSCs. The IOSCs consisting of an EBL of spin-coated WO3 on the active layer show an power conversion efficiency (PCE) of 2.07%. The WO3 has lower lowest unoccupied molecular orbital (LUMO) and higher highest occupied molecular orbital (HOMO) than MoO3, and the WO3 can improve the energy barrier between the active layer and the electrode. An IOSC under the optimized structure of ITO/ZnO/P3HT:PCBM/WO3/Ag exhibits open circuit voltage (Voc) of 0.573 V, short circuit current density (Jsc) of 6.35 mA/cm2, fill factor (F.F.) of 56.89% and PCE of 2.07% at AM 1.5G of 100 mW/cm2.