Coaxial Electrospinning Method for the Preparation of TiO2 @CdS/PVA Composite Nanofiber Mat and Investigation on its Photodegradation Catalysis.

TiO2 /PVA composite nanofiber mat was prepared via an electrospinning technology. SH-TiO2 -SiO2 hybrid particles and PVA solution were injected through a coaxial syringe, yielding a composite nanofiber mat. The as-prepared SH-TiO2 -SiO2 /PVA composite nanofiber mat was immersed in Cd(2+) cation solution and S(2-) anion solution in turn. Thus, yellow TiO2 @CdS/PVA composite nanofiber mats were prepared. By adjusting the number of times a mat was immersed in the Cd(2+) and S(2-) solutions, different amounts of CdS particles attaching to the mats were obtained. Both SH-TiO2 -SiO2 /PVA and TiO2 @CdS/PVA composite nanofiber mats were employed to catalyze the photodegradation of a model dye, methylene blue. The photodegradation performance could be greatly enhanced by the introduction of CdS particles anchoring onto TiO2 particles. The photodegradation efficiency reached 99.2% within 180 min. Also, the nanofiber mat could be recycled and reused at least 10 times. The photodegradation efficiency of TiO2 @CdS/PVA composite nanofiber mats remained 68.8% for 10 cycles.