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Graphical abstract Abstract Inspired by steaming bread, a novel three dimensional N and S co-doped reduced graphene oxide (3D NS-rGO) foam is fabricated via a gas foaming method similar to steaming bread procedure, in which (NH 4) 2 S 2 O 3 is selected as the foaming agent as well as N and S source. Such cross-linked 3D structure not only has the high specific surface area also enable more transport channels for electrons/ions transport. Furthermore, introducing of N and S-containing functional groups creates lattice defects in graphene, which provides more active sites where the Faradaic pseudocapacitance occurs. Consequently, the electrochemical test of 3D NS-rGO sample in a three-electrode system demonstrates a high specific capacity of 306.3 F g−1 at 1 A g−1, two times higher than that of rGO prepared at the same temperature. Moreover, 3D NS-rGO sample reveals the superb cycling stability with less than 2% capacitance loss after 10,000 cycles and it exhibits potential application for high performance supercapacitors. [ABSTRACT FROM AUTHOR]

Abstract: Branched alkylbenzenesulfonate gemini surfactants: sodium 6,6′-(propane-1,3-diylbis(oxy))bis(3-(2-propylpentyl)benzenesulfonate) (C8BC3C8B), sodium 6,6′-(propane-1,3-diylbis(oxy))bis(3-(3,5,5-trimethylhexyl)benzenesulfonate) (C9BC3C9B), and sodium 6,6′-(propane-1,3-diylbis(oxy))bis(3-(2,4,4-trimethylpentan-2-yl)benzenesulfonate) (T-C8BC3C8B) have been synthesized. Their interfacial activity and aggregation behavior in aqueous solution were studied by surface/interface tension measurement, electrical conductivity, isothermal titration microcalorimetry, 1H NMR spectroscopy, dynamic light scattering, steady-state fluorescence and cryogenic transmission electron microscopy. The critical aggregation concentration (CAC) and the minimum average surface area/molecule (A min) decrease with the decrease of the branching factor, i.e., in the order of T-C8BC3C8B, C8BC3C8B and C9BC3C9B. Moreover, alkyl side chain branches generate much more significant increases in CAC and A min for the gemini surfactants than single-chain surfactants. However, the branching factor does not change the air/water surface tension at CAC regularly. Instead, the air/water surface tension decreases with the increase of the carbon number of the hydrocarbon chains. In addition, it is noted that the branched gemini surfactants display high efficiency in reducing toluene/water interfacial tension. Interestingly, the increase in the branching factor leads to much more endothermic enthalpy of aggregation. All these three surfactants form spherical vesicles in aqueous solution and may present a parallel-displaced structure with a directional arrangement of the benzene ring in the vesicles. [Copyright &y& Elsevier]