Structural Approach for High Performance Solution-Processed Organic Solar Cells : Acetylene-incorporated Pyrene Derivatives

학위논문 (석사)-- 서울대학교 대학원 : 재료공학부(하이브리드 재료), 2012. 8. 박수영.To explore effects of acetylene-incorporation, acetylene-bridged small molecules were successfully synthesized and their photophysical, electrochemical, thermal, and photovoltaic device properties were investigated. The acetylene-incorporation was intended to benefit reduced HOMO-LUMO band gap through extended conjugation, and also the increased ionization potential of the molecules. It is well known that the former is effective in increasing Jsc, while the latter in increasing Voc. Consistent with the expectation and DFT calculation result, acetylene-incorporated pyrene derivatives exhibited planar back-bone, conjugation extension, enhanced light absorption, and low HOMO energy level. Combined with the advanced properties, solution-processed organic solar cells based on a blend of DPP-A-PY(HD) as a donor and [6,6]-phenyl-C71-butyric-acid-methyl-ester (PC70BM) as an acceptor exhibited as high as Voc of 0.85V, Jsc of 8.89 mA cm-2, FF of 41.7% and PCEs of 3.15%.Contents Abstract i Contents ⅲ List of Tables ⅴ List of Schemes ⅵ List of Figures ⅶ CHAPTER 1. Introduction 1 1-1. Background 1 1-2. Bulk-hetetojunction Organic Solar cells (BHJ OSCs) 3 1-2.1. Operation principles of OSCs 3 1-2.2. Device characterization 5 1-2.3. Bulk-heterojunction concept 7 1-2.4. Recent research trends in solution processible small molecule Donors 9 1-3. References 12 CHAPTER 2. Tetra-functionalized Pyrene Derivatives for Bulk-heterojunction Organic Solar Cells 15 2-1. Introduction 15 2-2. Experimental 17 2-3. Result and Discussion 28 2-4. Conclusions 40 2-5. References 41 CHAPTER 3. Mono-functionlized Pyrene Derivatives for Bulk-heterojunction Organic Solar Cells 43 3-1. Introduction 43 3-2. Experimental 45 3-3. Result and Discussion 55 3-4. Conclusions 70 3-5. References 71 Abstract in Korean 73 List of Presentations 75 List of Publications 76Maste