Reducible fabrication cost for P3HT-based organic solar cells by using one-step synthesized novel fullerene derivative

- Easily synthesized CHOC60 and CHAC60 were introduced.
- Keto and ester group have different effect on photovoltaic performances.
- CHOC60 shows comparable photovoltaic performances to PC61BM with low consumption.
- P3HT/CHAC60-based devices showed the highest PCE up to 3.15%.

The cyclohexanone-containing fullerene mono-adduct, abbreviated as CHOC60, was efficiently prepared through single-step Diels-Alder reaction with 2-(trimethylsilyloxy)-l,3-butadiene and fullerenes. After reduction and esterification, CHOC60 was further converted into cyclohexyl acetate functional fullerene mono-adduct, named as CHAC60, which showed excellent solubility in common organic solvents. P3HT-based bulk heterojunction organic solar cells (OSCs) were fabricated through a typical structure of ITO/PEDOT:PSS/P3HT:(CHOC60 or CHAC60)/Ca/Al. The composite ratios of P3HT and the fullerene derivatives were modified such as 1:0.5, 1:1 and 1:1.5 (w/w). The devices fabricated using CHOC60 or CHAC60 as acceptors achieved the power conversion efficiencies (PCEs) of 2.97% and 3.15%, respectively, which exhibited comparative photovoltaic performances with commercial PC61BM. Moreover, CHOC60-based devices significantly reduced the manufacturing cost by the simplified synthesis of CHOC60 with high yield and low fullerene consumption. The non-aromatic side chain radical CHOC60 and CHAC60 provide a new idea for the design of fullerene derivative acceptors.