Combination of Indene-C60 Bis-Adduct and Cross-Linked Fullerene Interlayer Leading to Highly Efficient Inverted Polymer Solar Cells

Abstract: A poly(3-hexylthiophene) (P3HT)-based inverted solar cell using indene-C60 bis-adduct (ICBA) as the acceptor achieved a high open-circuit voltage of 0.82 V due to ICBA’s higher-lying lowest unoccupied molecular orbital level, leading to an excep-tional power-conversion efficiency (PCE) of 4.8%. By incorporat-ing a cross-linked fullerene interlayer, C-PCBSD, to further modulate the interface characteristics, the ICBA:P3HT-based inverted device exhibited an improved short-circuit current and fill factor, yielding a record high PCE of 6.2%. Polymeric solar cells (PSCs) offer great potential for fabrication of large-area, lightweight, and flexible organic solar cells by using low-cost printing and coating technologies.1 A conventional bulk heterojunction (BHJ) PSC with an active layer sandwiched by a low-work-function aluminum cathode and a hole-conducting poly(3,4-ethylenedioxylenethiophene):poly(styrenesulfonic acid) (PEDOT:PSS