title: Constructing Ionic Liquid-Filled Proton Transfer Channels within Nanocomposite Membrane by Using Functionalized Graphene Oxide.
abstract: Herein, nanocomposite membranes are fabricated based on functionalized graphene oxides (FGOs) and sulfonated poly(ether ether ketone) (SPEEK), followed by being impregnated with imidazole-type ionic liquid (IL). The functional groups (acidic group or basic group) on FGOs generate strong interfacial interactions with SPEEK chains and then adjust their motion and stacking. As a result, the nanocomposite membranes possess tunable interfacial domains as determined by its free volume characteristic, which provides regulated location for IL storage. The stored ILs act as hopping sites for water-free proton conduction along the FGO-constructed interfacial channels. The microstructure at SPEEK-FGO interface governs the IL uptake and distribution in nanocomposite membrane. Different from GO and vinyl imidazole functionalized GO (VGO), the presence of acidic (-SO3H) groups confers the p-styrenesulfonic acid functionalized GO (SGO) incorporated nanocomposite membrane loose interface and strong electrostatic attraction with imidazole-type IL, imparting an enhanced IL uptake and anhydrous proton conductivity. Nanocomposite membrane containing 7.5% SGO attains the maximum IL uptake of 73.7% and hence the anhydrous conductivity of 21.9 mS cm(-1) at 150 °C, more than 30 times that of SPEEK control membrane (0.69 mS cm(-1)). In addition, SGOs generate electrostatic attractions to the ILs confined within SGO-SPEEK interface, affording the nanocomposite membrane enhanced IL retention ability.
authors.affiliation: School of Chemical Engineering and Energy, Zhengzhou University , Zhengzhou 450001, Peoples's Republic of China.
authors.forename: Wenjia
authors.initials: W
authors.lastname: Wu
authors.affiliation: School of Chemical Engineering and Energy, Zhengzhou University , Zhengzhou 450001, Peoples's Republic of China.
authors.forename: Yifan
authors.initials: Y
authors.lastname: Li
authors.affiliation: School of Chemical Engineering and Energy, Zhengzhou University , Zhengzhou 450001, Peoples's Republic of China.
authors.forename: Pingping
authors.initials: P
authors.lastname: Chen
authors.affiliation: School of Chemical Engineering and Energy, Zhengzhou University , Zhengzhou 450001, Peoples's Republic of China.
authors.forename: Jindun
authors.initials: J
authors.lastname: Liu
authors.affiliation: School of Chemical Engineering and Energy, Zhengzhou University , Zhengzhou 450001, Peoples's Republic of China.
authors.forename: Jingtao
authors.initials: J
authors.lastname: Wang
authors.affiliation: School of Chemical Engineering and Energy, Zhengzhou University , Zhengzhou 450001, Peoples's Republic of China.
authors.forename: Haoqin
authors.initials: H
authors.lastname: Zhang
keywords: anhydrous proton conductivitys; functionalized graphene oxide; interfacial microstructure; ionic liquid uptake and distribution; nanocomposite membrane