Photocatalytic and antifouling properties of electrospun TiO2 polyacrylonitrile composite nanofibers under visible light

Polyacrylonitrile and its TiO2 composites were electrospun into nanofibers in N, N'-dimethylformamide for photocatalysis and antifouling experiments. The resultants nanofibers were characterized using field emission scanning microscope, Fourier transform infrared spectroscopy, x-ray diffraction, x-ray photoelectron spectroscopy and contact angle analyses. Fourier transform infrared spectroscopy confirmed the formation of polyacrylonitrile-TiO2 composite nanofibers with their diameter ranging from 10 to 340 nm. The x-ray photoelectron spectroscopy results indicate the formation of O-Ti-C bonds on polyacrylonitrile-TiO2 matrix. polyacrylonitrile-TiO2 and polyacrylonitrile nanofiber surfaces showed superhydrophobicity with water contact angle of 155 +/- 1 and 154 +/- 1, respectively at 120 s. The photocatalytic properties of polyacrylonitrile nanofibers and polyacrylonitrile-TiO2 nanofibers were investigated under a simulated visible light source of 1000 W/m(2) using methylene blue. About 90% of methylene blue was degraded within 3 h of exposure using polyacrylonitrile-TiO2 nanofibers while 55% methylene blue degradation was achieved for polyacrylonitrile nanofibers. Photoluminescence experiment conducted on both materials showed that polyacrylonitrile-TiO2 could produce OH radicals 10-fold compared to polyacrylonitrile nanofibers. Antimicrobial tests were conducted using E. coli and Bacillus sp. The results showed that only polyacrylonitrile-TiO2 under visible light hindered the growth of these bacteria with a greater effect on the Gram-positive bacterium, Bacillus sp. The photo-degradation and microbial growth inhibition properties of polyacrylonitrile-TiO2 showed that the material could be used as an antifouling material under visible light.

Automated summary

Polyacrylonitrile and its TiO2 composites were electrospun into nanofibers for photocatalysis and antifouling experiments, showing superhydrophobicity. The polyacrylonitrile-TiO2 nanofibers exhibited higher degradation of methylene blue and production of OH radicals compared to polyacrylonitrile nanofibers under visible light. Additionally, the polyacrylonitrile-TiO2 nanofibers demonstrated antimicrobial properties, inhibiting the growth of bacteria, particularly Bacillus sp., under visible light conditions.