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Ce-doped MnOx/Ti electrocatalytic membrane electrodes were prepared by doping rare earth element Ce into manganese oxide (MnOx) via sol–gel method, and coated on the porous Ti substrate membrane electrode. In order to evaluate electrocatalytic activity of the Ce–MnOx/Ti electrode, a functional electrocatalytic membrane reactor (ECMR), which assembled a Ce–MnOx/Ti electrode as an anode and a stainless steel mesh as a cathode, has been employed for phenolic wastewater treatment. The results revealed that a new crystal form Ce2O3 appeared after doping Ce into the system, and the urchinlike morphology and smaller grain size of Ce–MnOx led the catalytic activity of the composite membrane electrode to improve. Moreover, the 25 mol% Ce–MnOx/Ti (C25MT) composite membrane electrode represented the best activity in the degradation of phenolic wastewater. During ECMR with C25MT operation under the conditions of 450 mg/L phenolic wastewater (500 mL), residence time of 5 min, pH of 1–13 and current density of 0.3–1.2 mA/cm2, the highest degradation efficiency of phenolic wastewater achieved in current density of 0.9 mA/cm2 and pH of 7, that is, the achieved remove rate of phenol, COD and TOC were 99.61, 93.12, and 84.23%, respectively. Finally, the effective reusability of C25MT composite membrane electrode was assessed, and a proposed reaction mechanism has been analyzed in the ECMR operation.

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.

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.

Alumina/basalt fiber mat composite (ABFMC) was fabricated by loading activated alumina (AA) on basalt fiber mat (BFM) via sol–gel method for fluoride removal. ABFMC and AA were characterized, and their performance for fluoride removal from aqueous solution was evaluated at different initial fluoride concentration and contact time. The loading capacity of AA on BFM increased with the increase in the sol viscosity, and the sol viscosity was optimized at 3.9 mPa s, whose corresponding loading percentage was 60.25 %. The results from the present study exhibit that ABFMC has shown good adsorption capacity for fluoride removal from aqueous solution. Experimental data revealed that the fluoride sorption on ABFMC was rapid, and 98.7 % fluoride removal was achieved within 30 min, whereas they were 96.8 % and 60 min in case of AA, respectively. The fluoride absorbed of ABFMC is well compared with that of most conventional materials and AA. The maximum of fluoride adsorbed on ABFMC was 1.872 mg/g. Adsorption isotherm analyses indicate that the adsorption of fluoride on ABFMC could be best described with the Langmuir isotherm, which suggested that the fluoride may create a monolayer layer on ABFMC. The adsorption kinetics was best described by the pseudo-second-order kinetic model followed by both intraparticle diffusion and film diffusion as the rate-controlling rate step.