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Designing electrode materials with excellent comprehensive properties was of top priority in promoting development of flow electrode capacitive deionization (FCDI). To date, most FCDI studies involved the application and modification of carbon-based materials, which suffered the contradiction between rheological behavior and electrochemical performance. In this study, a Na+superionic conductor (NASICON) sodium vanadium fluorophosphate@reduced graphene oxide (NVOPF@rGO) was synthesized and applied as a flow electrode in FCDI. Benefiting from the confinement effect of the three-dimensional (3D) reduced graphene oxide (rGO) network, thin and uniform NVOPF nanosheets formed and provided abundant active sites for adsorbing Na+. Moreover, the interconnected rGO network formed a 3D conductive network for Na+and electron transport. Compared with an activated carbon (AC)–AC system (AC was used as an anode and a cathode), a NVOPF@rGO–AC system (NVOPF@rGO was used as a cathode and AC was used as an anode) exhibited preferable dispersibility and stability of electrode dispersion, lower internal resistance, higher desalination rate, and lower energy consumption. Besides, the average salt adsorption rate (ASAR) reached 5.32 μg·cm–2·min–1by adjusting the concentration of the electrode (4.73 wt %), the flow rate of the electrode (25 mL·min–1), and the operation voltage (1.6 V). This study demonstrated the potential of faradic flow electrodes for promoting the development and application of FCDI.

The cleavage of the linkage bonds among the C9 units in lignin molecules via selective oxidation method to obtain small-weight aromatic compounds is an important way to lignin valorisation. In this study, the cleavage pathways of bonds in a lignin model compound, GGE (guaiacylglycerol-?-guaiacyl ether), by the reactive oxygen species (ROS) in situ generated through electrochemical oxygen reduction reaction (ORR) in an aprotic ionic liquid ([BMIM]BF4) was investigated. The results indicated that when the main ROS was ·OOH, coniferyl alcohol, guaiacol and vanillin were detected as the degradation products which is supposed to be caused by ?-O-4 bonds cleavage; Otherwise, when HO2?was the main ROS, coniferyl alcohol could not be detected and the degradation reaction is believed to be trigerred by C?-C?bonds cleavage.