Conjugated Random Copolymers Composed of Rearranged Pechmann Dye and Diketopyrrolopyrrole

1. Conjugated Random Copolymers Composed of Rearranged Pechmann Dye and Diketopyrrolopyrrole with Panchromatic Absorption for Efficient Polymer Solar Cells 서상덕,조원호* 서울대학교 재료공학부 • Optical and electrochemical properties Ca/Al Polymer:PC70BM PEDOT:PSS ITO J. Am. Chem. Soc.2012, 134, 5432 Nat. Phot.2012, 6, 180 aCalculated from ELUMO = EHOMO + Egopt • Short wavelength absorption (RPD) + Long wavelength absorption (DPP) • → Panchromatic absorption (PDPPRPD3T) Glass • Crystallinity of polymers (300) (400) (010) (200) ↓ ↓ ↓ ↓ • RPD in random copolymer (PDPPRPD3T) does not disturb the crystallization of DPP based homopolymer. Results • Photovoltaic properties • Synthesis • Synthesis of monomers Introduction • Cross coupling reactions • Previous strategies for panchromatic absorption • Morphology of active layers (a) PDPPRPD3T:PC70BM (b) PDPP3T:PC70BM • Morphology optimization will be • performed through further work. • Tandem cell • Ternary blend Conclusions • PDPP3T, PDPPRPD3T, PRPD3T are successfully synthesized and PDPPRPD3T • shows panchromatic light absorption. • PDPPRPD3T shows the PCE of 2.40% with VOC of0.75 V, JSC of 5.55 mA/cm2 and FF of 0.58. Difficult fabrication of tandem device Difficult control to achieve optimum morphology • Rearranged Pechmann Dye (RPD) and Diketopyrrolopyrrole (DPP) • Electron deficient nature • Similar chemical structure • Complimentary light absorption • - RPD: short wavelength light absorption • - DPP: long wavelength light absorption DPP RPD → Suitable properties for random copolymer as co-electron accepting unit Objectives (300) (200) ↓ ↓ • To synthesize random copolymer composed of RPD and DPP as • co-electron accepting units for high performance polymer solar cells • To compare the optical, electrochemical and photovoltaic properties of random copolymer with those of the corresponding homopolymers (300) (200) ↓ ↓ (100) (100) (100) ↓ ↓ ↓ (b) (a)