Preparation, characterization, and properties of nano-TiO2/silk fibroin hybrid films by sol-gel processing

By sol-gel processing, the regenerated nano-TiO(2)/SF (silk fibroin) hybrid films were synthesized using different ratios of TiO(2) to SF. The experimental results revealed that the nano-TiO(2) particles were well dispersed in the regenerated SF. The diameter of the nano-TiO(2) particles processed by sol-gel method was about 80 nm. Through Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray energy dispersive spectrometer (EDS), Thermogravimetric analysis (TGA), and Derivative thermogravimetry (DTG), the structures and properties of these hybrid films were characterized. The XRD measurement indicated that the crystal structures of the hybrid films were transited from typical Silk I to typical Silk II. However, it was found that excessive increase in the content of nano-TiO(2) led to the breakage of the crystal structures of the hybrid films. The FTIR and EDS analysis showed that new bonds were formed between the nano-TiO(2) particles and the SF. Through TGA and DTG, it was demonstrated that the heat transition temperature of the hybrid films was also enhanced.