Carbohydrate-attached fullerene derivative for selective localization in ordered carbohydrate-block-poly(3-hexylthiophene) nanodomains

A carbohydrate-based fullerene derivative (AcMal(7)-C-61) is designed, synthesized and applied to a lamellar-forming high-chi block copolymer system, poly(3-hexylthiophene)-block-peracetylated maltoheptaose (P3HT-b-AcMal(7)), to actualize an ordered donor/acceptor (D/A) network. A well-defined D/A lamellar structure of the P3HT-b-AcMal(7) :AcMal(7)-C-61 blend with sub-10 nm domain features is achieved upon thermal annealing. The AcMal(7)-C-61 molecules are localized in the phase-separated AcMal(7) nanodomains without causing the formation of fullerene crystals while maintaining the lamellar morphology up to 1:0.5 (D:A) blending ratio. The cross-sectional TEM observation and GISAXS measurement reveals that the P3HT-b-AcMal(7) tends to spontaneously organize into lamellar structures oriented perpendicular to the film surface at the air/film interface while the domain orientation at the bottom interface depends on the nature of the substrate.

Automated summary

A carbohydrate-based fullerene derivative was synthesized and applied to a lamellar-forming high-chi block copolymer system to realize an ordered donor/acceptor network. Through thermal annealing, a well-defined D/A lamellar structure with sub-10 nm domain features was achieved. The molecules of the derivative were localized in phase-separated nanodomains without disrupting the lamellar morphology, showing potential for new strategies in blend synthesis.