Xiaoping Liang

PEO/PVDF-based gel polymer electrolyte by incorporating nano-TiO2 for electrochromic glass

To develop high performance mixed matrix gel polymer electrolyte, the synergistic effect of blending PVDF (PEO/PVDF weigh ratio of 85:15) and adding nano-TiO2 (0.5–2 wt.%) to traditional monomer poly (ethylene oxide) was investigated. Thermogravimetric analysis indicated that poly (ethylene oxide)/poly (vinylidene fluoride) blend had an excellent thermal performance. X-ray diffraction analysis revealed that poly (ethylene oxide)/poly (vinylidene fluoride) blend leads to lower crystallinity and the amorphicity of corresponding gel polymer electrolyte increases with increasing nano-TiO2 concentration. The maximum ionic conductivity (2.12 × 10−6 and 6.37 × 10−6 S/cm) of poly (ethylene oxide)/-(TiO2)0.5 and poly (ethylene oxide)/poly (vinylidene fluoride)/-(TiO2)0.5 gel polymer electrolyte at room temperature (25 °C) were obtained, respectively. The prepared poly (ethylene oxide)/poly (vinylidene fluoride)-TiO2 gel polymer electrolyte demonstrated about 2.6 and 1.8-fold increment in the fracture strength as compared to that of poly (ethylene oxide) gel polymer electrolyte and poly (ethylene oxide)-TiO2 gel polymer electrolyte. The average transmittance of poly (ethylene oxide)/poly (vinylidene fluoride)-TiO2 gel polymer electrolyte was about 90 % in the visible region. With good electrical, mechanical and optical performance, it is very suitable for being applied in electrochromic glass.Graphical Abstract

Microstructure and photocatalytic properties of Ag/Ce4+/La3+ co-modified TiO2/Basalt fiber for ammonia–nitrogen removal from synthetic wastewater

Ag/Ce4+/La3+ (1, 3, and 5 wt.%) co-modified titanium dioxide powder and modified Titanium dioxide coated basalt fiber photocatalysts were prepared via sol–gel method. The properties of the photocatalysts were characterized in detail by using transmission electron microscopy, field-emission scanning electron microscopy, UV–visible absorption spectra, X-ray powder diffraction, X-ray photoelectron spectroscopy. The results showed that the crystal of titanium dioxide photocatalyst transformed from anatase/rutile mixture phase to pure anatase phase, and the anatase crystallites size decreased after co-modifying by Ag/Ce4+/La3+. In comparison, Ag/Ce4+/La3+ co-modified titanium dioxide exhibited higher degradation efficiency than that of Ce4+/La3+ modified titanium dioxide and Ag modified titanium dioxide due to the synergistic effect of Ce4+/La3+ and Ag0. Moreover, 3% Ag/Ce4+/La3+-TiO2 coated basalt fiber photocatalyst represented the best activity in the degradation of ammonia nitrogen wastewater. After 6 h degradation reaction, the concentration of ammonia nitrogen decreased from 60.4 mg/L to 2.8 mg/L, and the degradation rate of ammonia nitrogen reached 95.3%, about 74% of total nitrogen was removed during the process, whereas were 93.9 and 70.7% in case of 3% Ag/Ce4+/La3+-TiO2 powder, respectively.Graphical Abstract