Cellulose acetate nanofibers with photochromic property: Fabrication and characterization

Photochromic nanofibers were fabricated by electrospinning the complex of cellulose acetate (CA)–1′,3′,3′-trimethyl-6-nitrospiro (2H-1-benzopyran-2,2′-indoline) (NO2SP) and their photochromic properties were investigated. The as-spun nanofibers were characterized by infrared spectra (IR) and the results showed a significant hydrogen bonding reaction between CA and NO2SP. Incorporated NO2SP was found to exert no effect on the nanofiber morphology. Through monitoring the color change and the water contact angle of the CA–NO2SP nanofibrous mat, the reversible photochromic property of the nanofibers was testified. The results of ultraviolet–visible (UV–vis) spectrophotometry and fluorescence microscopy indicated that NO2SP could endow electrospun fibers with good photochromic and fluorescent properties. Photochromic nanofibers with excellent photosensitivity have great potentials for the applications in optical devices and/or biosensors.