The Study on Efficiency Enhancement of Flexible Polymer Solar Cell by Blending PCPDTBT into Active Layer and Incorporating a Layer of Graphene

• Main Authors: GUAN-YOU CHEN, 陳冠佑
• Other Authors: JHEN-FANG OU
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/52994318287112770474

碩士 === 國立勤益科技大學 === 化工與材料工程系 === 102 === The plastic film exhibit high optical transmittance, flexible, light weight, low cost, resistance to shocks, unbreakable and easy to carry. So the plastic film is considered to be a candidate for flexible polymer solar cell. We introduced graphene coating into flexible photovoltaic cell. We study the effect of preparation conditions of the active layer on photovoltaic performance by changing the concentration of graphene. The cell structures were (A) PET/ITO/PEDOT:PSS/Graphene/P3HT:PCBM/Ca/Al and (C) PET/ITO/PEDOT:PSS/Graphene/P3HT:PCPDTBT:PCBM/(0.7:0.3:1、0.8:0.2:1、0.9:0.1:1)/Ca/Al. On the other hand, we investigated the effect of adding PCPDTBT (poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b’]-dithiophene)-alt-4,7(2,1,3-benzothiadiazole)]) into the active layer on the characteristics of flexible polymer solar cell. The cell structure was (B) PET/ITO/PEDOT:PSS/P3HT:PCPDTBT:PCBM(0.7:0.3:1、0.8:0.2:1、0.9:0.1:1)/Ca/Al and (D) PET/ITO/PEDOT:PSS/P3HT:PCPDTBT:PCBM(1:0.06:1、1:0.10:1、1:0.13:1)/Ca/Al. We used the UV-Vis, PL, SPM, FE-SEM and solar simulator to measure the absorbance, PL intensity, surface morphology, roughness and power conversion efficiency, respectively.The device (A), the short circuit current density was increased from 0.39 mA/cm2 to 0.55 mA/cm2, an increase of 41%. The power conversion efficiency was increased from 0.37% to 0.77%, an increase of 108%. The P3HT:PCPDTBT:PCBM with weight ratio of 0.7:0.3:1、0.8:0.2:1、0.9:0.1:1 was added into the active layer in the device (B) and (C), respectively. Wherein the device (C) the graphene layer was incorporated coated between PEDOT:PSS and active layer. When the composition of active layer of device (B) and (C) were 0.9:0.1:1, the short circuit current density were increased to 0.71 mA/cm2 and 0.73mA/cm2, an increase of 82% and 84.6%, respectively. The power conversion efficiency were increased to 0.97% and 1.07%, an increase of 162% and 189%, respectively. From these results, blending PCPDTBT into active layer and incorporating a layer of graphene in flexible polymer solar cells resulted in more photo-induced charge carrier generation due to the more broad absorption range of PCPDTBT. The composition of active layer of device (D) were P3HT:PCPDTBT:PCBM by the weight ratio of 1:0.06:1、1:0.10:1、1:0.13:1. When the composition of active layer was 1:0.06:1, the short-circuit current density of device (D) was increased to 0.93 mA/cm2, an increase of 138%. The power conversion efficiency of the device was increased to 1.75%, an increase of 372%. From these data, device (D) exhibite the best performance in all of the investigated devices.