Electrospinning preparation of a H 4 SiW 12 O 40 /polycaprolactam composite nanofibrous membrane and its greatly enhanced photocatalytic activity and mechanism

• Published in: RSC advances 2016, Vol.6 (15), p.12491-12496
• Main Authors: Li, Wei, Li, Tingting, Ma, Xuegang, Li, Yuanliang, An, Libao, Zhang, Zhiming
• Format: Article
• Language: English
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/C5RA25550C

H 4 SiW 12 O 40 /polycaprolactam (PA6) composite nanofibrous membranes with a minimum average diameter of ∼70 nm were prepared by an electrospinning technique. Characterization with Fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS) indicated that H 4 SiW 12 O 40 has been successfully loaded into the PA6 membrane and its Keggin structure was intact. The as-prepared H 4 SiW 12 O 40 /PA6 membranes exhibited greatly enhanced photocatalytic efficiency (≥96.0%) and excellent reusability in the degradation of methyl orange (MO) under ultraviolet irradiation, which may be attributed to the synergistic effect of PA6 and H 4 SiW 12 O 40 . The photocatalytic process was likely to be driven by the reductive pathway with a much faster degradation rate due to the electron donation from PA6 to H 4 SiW 12 O 40 . The hydrogen bonds between H 4 SiW 12 O 40 and PA6 could enhance the stability of H 4 SiW 12 O 40 in the membrane, so that there was nearly no loss of photocatalytic activity of the catalyst after three cycles of reactions. In view of this, H 4 SiW 12 O 40 /PA6 composite nanofibrous membranes exhibit potential for practical applications to eliminate organic pollutants from wastewater.