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[Display omitted] • Dopamine-functionalized carbon interface enhances interfacial activity. • Boron and oxygen are codoped to optimize the capacitive behavior of carbon materials. • The inside-out pore creating method of body phase improves the activation efficiency. As a typical double-layer capacitive electrode material, carbon nanomaterials show desirable application potential in the field of capacitive deionization (CDI) and supercapacitors (SCs). In this work, interfacial functional groups and B\O co-doping defects are simultaneously introduced into multi-chamber carbon with confinement effect, and their practical applications in CDI and flexible capacitors are also studied. Specifically, the oxygen-rich carbon source and boron source, dissolved and mixed completely via co-crystallization method, released amount of gas during the pyrolysis process to produce multi-chamber honeycomb-like carbon with ultrathin walls, which were further introduced into abundant interfacial functional groups by dopamine to optimize the carbon surface. At the same time, part of boron atoms entered the carbon lattice to form boron doping at high temperature, followed by the integration with the oxygen heteroatoms in carbon source to generate abundant boron and oxygen codoping defects. The as-prepared diatomic defects by the synergistic effect promote the wettability and pseudocapacitance of the material. In addition, the derived carbon materials are endowed with good hydrophilic ability and surface activity under the modification of dopamine functional groups. The ideal hydrophilic ability ensures that the porous structure of material can be infiltrated by electrolyte to provide large effective specific surface area, which enhances the electrical double-layered capacity. The interfacial functional groups also offer additional pseudocapacitance, so as to improve the ion adsorption capacity of PDA-BOC. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple and non-destructive three-electrode EIS method was established for ACF. • Equivalent circuits and one-dimensional EDLC electrodes were constructed. • Weaving patterns of ACF affect their electrochemical performance. • Volumetric adsorption capacity (VAC) and capacitance (VSC) are positively related. • Knitted ACFs show lower energy consumption than woven ACFs. Activated carbon fibres (ACFs) are successful electrode materials for capacitive deionization (CDI) owing to their excellent electrochemical properties and commercial availability, for example, with knitted or woven morphology patterns. However, the lack of a common and effective analytical framework to analyse the performance of ACFs is hindering further progress in the area. This study establishes an electrochemical impedance-based method to detect and investigate the electrochemical properties of ACF materials without destroying their original weaving patterns. Five commercial ACFs with two distinct patterns and similar specific surface areas were investigated. Data from electrochemical impedance spectroscopy (EIS) are compared to the desalination performance and energy consumption of the ACFs in a CDI cell. The weaving pattern played a role in the electrochemical properties and desalination performance. The volume-salt adsorption capacities in CDI were related to the volume-specific capacities in EIS, however, there was no significant difference between knitted and woven materials. Linked to EIS features, knitted ACFs consume less energy than woven ACFs for removing the same amount of NaCl from water. These results provide ACF researchers with a new, effective, and readily available approach for measuring the electrochemical performance of ACF materials via EIS. [ABSTRACT FROM AUTHOR]

[Display omitted] • We report the synthesis and study of porous carbon derived from ZIF-67 for electrosorption study of NaCl. • The electrochemical analysis confirms the significant increase in the specific capacitance of PC-ZIF-67. • PC-ZIF-67 exhibits high electrosorption capacity of 28.13 mg/g. • The values of SAC fit well with Freundlich adsorption isotherm. Capacitive deionization (CDI) is an emerging and environmentally friendly technology for water desalination with promising future. The electrode material with high electrosorption performance is critical in CDI application. Here, we report the synthesis and study of porous carbon derived from zeolitic imidazolate framework-67 (ZIF-67) for electrosorption study of NaCl. The morphology and graphitic degree are analysed by X-ray diffraction and scanning electron microscope. The electrochemical analysis is performed using cyclic voltammetry and galvanostatic charge-discharge confirming the significant increase in the specific capacitance of porous carbon derived from ZIF-67. Further, the porous carbon derived from ZIF-67 was studied for deionization of water and exhibits high electrosorption capacity of 28.13 mg/g for initial salt concentration of 800 mg/L at 1.4 V. [ABSTRACT FROM AUTHOR]