Herein, we present an innovative graphene oxide (GO)-induced strategy for synthesizing GO-based metal-organic-framework composites (Co-BTC@GO) for high-performance supercapacitors. 1,3,5-Benzene tricarboxylic acid (BTC) is used as an inexpensive organic ligand for the synthesis of composites. An optimal GO dosage was ascertained by the combined analysis of morphology characterization and electrochemical measurement. The 3D Co-BTC@GO composites display a microsphere morphology similar to that of Co-BTC, indicating the framework effect of Co-BTC on GO dispersion. The Co-BTC@GO composites own a stable interface between the electrolyte and electrodes, as well as a better charge transfer path than pristine GO and Co-BTC. A study was conducted to determine the synergistic effects and electrochemical behavior of GO content on Co-BTC. The highest energy storage performance was achieved for Co-BTC@GO 2 (GO dosage is 0.02 g). The maximum specific capacitance was 1144 F/g at 1 A/g, with an excellent rate capability. After 2000 cycles, Co-BTC@GO 2 maintains outstanding life stability of 88.1%. It is expected that this material will throw light on the development of supercapacitor electrodes that hold good electrochemical properties.

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To explore the effect of spacer structure on the adsorption capability of organo-vermiculites (organo-Vts), a series of aza-containing gemini surfactants (5N, 7N and 8N) are applied to modify Na-vermiculite (Na-Vt). Large interlayer spacing, strong binding strength and high modifier availability are observed in organo-Vts, which endow them with superiority for the adsorption of 2-naphthol (2-NP) and bromophenol blue (BPB). The maximum adsorption capacities of 5N-Vt, 7N-Vt and 8N-Vt toward 2-NP/BPB are 142.08/364.49, 156.61/372.65 and 146.50/287.90 mg/g, respectively, with the adsorption processes well fit by the PSO model and Freundlich isotherm. The quicker adsorption equilibrium of 2-NP than BPB is due to the easier diffusion of smaller 2-NP molecules into the interlayer space of organo-Vts. Moreover, stable regeneration of 7N-Vt is verified, with feasibility in the binary-component system that is demonstrated. A combination of theoretical simulation and characterization is conducted to reveal the adsorption mechanism; the adsorption processes are mainly through partition processes, electrostatic interaction and functional interactions, in which the spacer structure affects the interlayer environment and adsorptive site distribution, whereas the adsorbate structure plays a role in the diffusion process and secondary intermolecular interactions. The results of this study demonstrate the versatile applicability of aza-based organo-Vts targeted at the removal of phenols and dyes as well as provide theoretical guidance for the structural optimization and mechanistic exploration of organo-Vt adsorbents.