In this study, the Sulfonated graphene oxide (SGO)/Fe 3 O 4 nanosheets were synthesized by hydrothermal method and incorporated into blend sulfonated poly(ether ether ketone) (SPEEK)/poly(vinyl alchole) (PVA) matrix with different weight percent of (SGO)/Fe 3 O 4 nanosheets. The performances of prepared membranes were investigated by water uptake, membrane swelling, mechanical and thermal stability, proton conductivity, methanol permeability and DMFC test. It was found that the water uptake and tensile strength of SPEEK membrane increased and proton conductivity and power density decreased by 2 blending with PVA. Incorporation of SGO/Fe 3 O 4 nanosheets into SPEEK/PVA matrix enhanced mechanical stability, proton conductivity and methanol barrier properties of membrane. The SPEEK/PVA/SGO/Fe 3 O 4 nanocomposite membrane with optimal nanosheets content (5 wt%) exhibits low methanol permeability (8.83 × 10 −7 cm 2 s -1 ), high tensile strength (51.2 MPa), high proton conductivity (0.084 S cm -1 at 25°C) and high power density (122.7 mW cm -2 at 80°C) and suggests its potential application in DMFCs.

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A novel, high-efficiency, and cost-effective series of sulfonated poly­(phthalazinone ether ketone)/sulfonated titanium dioxide@toluene diisocyanate@ethylenediamine (SO3H−TiO2@TDI@EN-SO3H) nanocomposite membranes is designed to enhance the proton conductivity and methanol barrier of the proton exchange membrane (PEM). The nanocomposite membranes were prepared via a facile one-step process of the solution casting method. The presence of organic–inorganic SO3H–TiO2@TDI@EN-SO3H nanoparticles improved the performance of the nanocomposite membranes in terms of mechanical stability, proton conductivity, methanol permeability, and selectivity. We used toluene diisocyanate (TDI) as a linker to exploit the properties of sulfonated TiO2 and sulfonated ethylenediamine (EN-SO3H) nanoparticles. These nanoparticles act as Lewis and Brønsted acids simultaneously because of the presence of sulfonamide, TiO2, and SO3H groups, which increase the kinetics of the reaction between the membrane and electrode, improving the performance of the direct methanol fuel cell (DMFC). The DMFC, which is assembled using the nanocomposite membrane with 5 wt % SO3H–TiO2@TDI@EN-SO3H nanoparticle (MSN5) membrane, exhibited a maximum power density of 59.22 mW cm–2 during testing because of high proton conductivity and low methanol permeability. The MSN5 membrane is a promising PEM for DMFCs.

-Zeolite beta nanoparticles were used as a new asphaltene adsorbent for reducing asphaltene deposition during fluid injection into a silica sand pack. At first, the asphaltene adsorption efficiency and capacity of zeolite beta nanoparticles were determined by UV-Vis spectrophotometer. It was found that the proper concentration of nanoparticles for asphaltene adsorption was 10 g/L and the maximum asphaltene adsorption onto zeolite beta was 1.98 mg/m 2 . Second, two dynamic experiments including co-injection of crude oil and n-heptane (as an asphaltene precipitant) with and without use of zeolite beta nanoparticles in the sand pack was carried out. The results showed that the use of zeolite beta nanoparticles increased the permeability ratio and outlet fluid's asphaltene content about 22% and 40% compared to without use of nanoparticles, respectively. Moreover, a model based on monolayer asphaltene adsorption onto nanoparticles and asphaltene deposition mechanisms including surface deposition, entrainment and pore throat plugging was developed to determine formation damage during co-injection of crude oil and n-heptane into the sand pack. The proposed model presented good prediction of permeability and porosity ratios with AAD% of 1.07 and 0.07, respectively.

Novel proton-exchange membranes (PEMs) based on sulfonated poly(ether ether ketone) (SPEEK) and two-dimensional sulfonated niobium disulphide (S-NbS2) nanoflakes are synthesized and used for vanadium redox flow batteries (VRFBs).

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