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The interaction between novel saponification products (RCOONa or RCOOK) of Robinia pseudoacacia seed oil and cetyltrimethyl ammonium bromide (CTAB) in aqueous solution have been investigated by surface tension method at 25°C. The critical micelle concentration (cmc) of RCOONa/CTAB and RCOOK/CTAB mixture were measured. The surface properties of saponification products, CTAB as well as the mixed system were explored and compared. The composition, activity coefficient of mixed micelle, and the interaction parameters (βσ, βM) between surfactants were estimated according to the Regular Solution Theory, the Clint's model and the Rubingh's model in the framework of pseudophase separation model. The experimental results suggested that both RCOONa and RCOOK have synergism with CTAB in mixed micelle formation and surface tension reduction through calculating of βσ and βM in the mixed system. This could be attributed to the strong interaction between the head groups with opposite charges in the surfactant molecules. [ABSTRACT FROM AUTHOR]

As an organic pseudocapacitive active material, 2, 3‐Dichloro‐1, 4‐naphthoquinone (DNQ) was used in supercapacitors. Graphene with unique structures and high electrical conductivity acts as substrate. DNQ non‐covalently modified graphene composite material (DNQ@rGO) was synthesized through the simple solvothermal synthesis. The redox reaction between naphthol and naphthoquinone occurs on reduced graphene oxide(rGO), which forms an ideal pseudocapacitance without destroying its sp2 network. The optimal DNQ@rGO electrode material obtained the specific capacitance of 361.2 Fg−1 at 5 mV s−1 in 1 mol L−1 H2SO4 and exhibited excellent rate capability (capacitance retention of 87.5 % at 100 mV s−1) in the three‐electrode system. We also prepared holey layered oxygen‐rich graphene hydrogels (HLGH) material, whose electrochemical performance is superior to traditional three‐dimensional (3D) graphene hydrogels (GH). Finally, two asymmetric supercapacitors (ASCs) were assembled by using the DNQ@rGO (positive electrode), the HLGH and GH (negative electrode). The results show that the ASC with HLGH as negative electrode achieved the high energy and power densities due to the perfect matching of capacitance and kinetics between the positive and negative electrodes. The specific capacitance was almost no loss after 4700 cycles, showing the excellent stability. [ABSTRACT FROM AUTHOR]

In this report, the theory based on thin-layer cyclic voltammetry (TLCV) for consecutive electron transfer (ET) across the interface between two immiscible electrolyte solutions (ITIES) is well developed and experimentally verified. The voltammetric responses to multistep electron transfer at the ITIES are predicted by numerical simulations. Moreover, the impact of empirical parameters on the shape of the multistep current-voltage curve has been examined. The results obtained not only give information regarding the effect of the concentration ratio of the reactants in two phases and the thin-layer thickness on multistep electron transfer, but also prove the excellent agreement between simulations and experiments. The model system of two-step electron transfer of ZnTPP/[[Fe[(CN).sub.6]].sup.4-] was studied, indicating that the Bulter-Volmer (B-V) theory is suitable for the consecutive electron transfer. Thus, TLCV is demonstrated to be a useful means for investigating the kinetics of heterogeneous consecutive ET. 10.1021/ac1016997

The electrochemical oxidation of anodic Ti, Fe, Cd, Sn, and Pb (=M) into acetonitrile solutions of N,N'-bis(salicylidene)-o-phenylenediamine [SalophH2] gives the corresponding M(Saloph) complexes in high yield. The mechanism of the electrochemical reactions is discussed. SalophH2 forms complexes (1:1 molar ratio) with titanium, iron, cadmium, tin, and lead ions. The complexes have been characterized by elemental analyses, molar conductivity measurements, and infrared and electronic spectral data. The SalophH2 complexes of iron(II) and cadmium(II) have been further identified by 1H-NMR and mass spectra. [ABSTRACT FROM AUTHOR]