Flexible Solar Yarns with 15.7% Power Conversion Efficiency, Based on Electrospun Perovskite Composite Nanofibers

A flexible perovskite solar yarn with an impressive active lifetime (>216 h) and an exceptional photon conversion efficiency is prepared under ordinary conditions. The champion device demonstrates an average linear mass density of 0.89 mg cm(-1)and can be bent over a loop diameter of 2.5 mm, with a negligible efficiency loss. Photoactive nanofibers composed of a polyvinylpyrrolidone (PVP) central strain and a perovskite phase on the surface (with average grain size of 275 +/- 14.3 nm), are prepared by electrospinning, at 18 kV, relative humidity of 75%, and a temperature of 25 degrees C. This bilayered configuration promises superior mechanical strength and flexibility, together with an excellent photovoltaic character, compared with their dip coated counterparts. Photoactive perovskite nanofibers are incorporated into a plied-solar yarn, with an organic hole-conductive layer, poly(3-hexylthiophene-2,5-diyl)-coated on silver yarn electrode, and a composite electron conductive layer, phenyl-C-61-butyric acid methyl ester (PC61BM)-SnO(2)coated on a carbon yarn. An individual double-twisted solar yarns yields 15.7% champion power conversion efficiency, while a 30.5 mm x 30.5 mm active area of plain-woven fabric generates a maximum power density of 1.26 mW cm(-2)under one sun (1000 W m(-2)) solar illumination.