•Anhydrous PEM made of different ILs, SPEEK, and mesoporous SiO2 are prepared.•Influences of different ILs on the properties of composite membranes are studied.•The conductivity of membranes displayed a positive correlation with hopping sites.•The conductivity of 15.0 mS/cm was obtained for SP/SiO2-7.5/[BMIm][BF4]-50 membrane.•IL leaching of membranes decreased significantly after doping with mesoporous SiO2.Anhydrous proton conducting membranes made of different ionic liquids (ILs), sulfonated poly (ether ether ketone) (SPEEK), and mesoporous silica (SiO2) are successfully prepared. Influences of different ionic liquids on the properties of composite membranes doped with 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIm][BF4]), 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([BMIm][Tfo]), 1-butyl-3-methylimidazolium chloride ([BMIm]Cl), diethylmethylammonium trifluoromethanesulfonate ([dema][Tfo]), and 1-ethylimidazolium trifluoromethanesulfonate ([EIm][Tfo]) ionic liquids are described. Fourier transform infrared spectroscopy (FT-IR) analysis showed that there were interactions between ionic liquids, SPEEK and mesoporous silica. IL leaching studies demonstrated that IL loss decreased significantly after doping with SiO2. The proton conductivity study showed that both anions and cations of IL influenced the proton conductivity of the composite membranes. Proton conductivity of composite membranes displayed a positive correlation with the number of hopping sites within IL cation structures. Of all the conducting membranes studied, SP/SiO2-7.5/[BMIm][BF4]-50 showed the highest anhydrous proton conducting ability (15 mS cm−1 at 200 °C). Therefore, it is expected to find applications in proton exchange membrane fuel cells under medium temperature, anhydrous conditions.Download high-res image (220KB)Download full-size image

•Novel electrocatalyst PtVSnO2/C is synthesized by a modified Bönnemann method.•Adding Sn and V changes the geometric and electronic structure of Pt.•PtVSnO2/C improved catalytic activity and the ability of resisting CO poisoning.A novel carbon-supported Pt-V-SnO2 catalyst is prepared by a modified Bönnemann method. Pt/C, PtV/C, and PtSnO2/C are used for comparative analysis to study PtVSnO2/C in terms of its structure and electrocatalytic activity for the ethanol oxidation reaction (EOR). Characterization of its structural properties by X-ray diffraction (XRD) and transmission electron microscopy (TEM) is described. It is shown that the Pt lattice parameter decreases with the addition of V but increases with the addition of Sn in the PtVSn/C catalyst. TEM analysis reveals that the prepared catalyst particles are in the nanosize range (2-4 nm). EDS confirms the atomic compositions of the synthesized catalysts to be similar to the nominal values. The electrocatalytic activities are characterized by cyclic voltammetry (CV) and amperometric i-t curve measurement (i-t) techniques. The incorporation of a small amount of V in the PtSnO2/C electrocatalyst leads to higher activity for the ethanol oxidation reaction at room temperature. According to the Arrhenius equation, the apparent activation energy of PtVSnO2/C (3:1:3) for EOR is the lowest among the studied catalysts, which may be attributed to a synergistic effect between Sn and V.