Vortex-Aligned Ordered Film of Crystalline Fullerene C 70 Microtubes with Enhanced Photoluminescence and Photovoltaics Properties.

Crystalline fullerene C ₇₀ microtubes (FMTs) were produced employing ultrasound-assisted liquid- liquid interfacial precipitation (ULLIP) technique at the interface between fullerene C ₇₀ solution in 1,2 dichlorobenzene (DCB) and isopropanol (IPA) at 15 °C. Using the vortex-flow motion of the subphase water (also called Vortex-Langmuir-Blodgett technique), the FMTs were aligned and homogeneous films were prepared at the air-water interface. The aligned FMTs film exhibited enhanced photoluminescence (PL) with PL intensity ~5 times higher than that of the pristine C ₇₀ . Moreover, the aligned FMT film showed better photovoltaics properties compared with randomly oriented FMTs and pristine C ₇₀ film obtained from the spin coating. The compact, directional orientation and proper surface coverage of the FMT film enhanced the charge transport properties in the photovoltaic device.