By using three-dimensional (3D) tubular molybdenum disulfide (MoS2) as both an active material in electrochemical reaction and a framework to provide more paths for insertion and extraction of ions, PANI nanowire arrays with a diameter of 10-20 nm can be controllably grown on both the external and internal surface of 3D tubular MoS2 by in situ oxidative polymerization of aniline monomers and 3D tubular MoS2/PANI hybrid materials with different amounts of PANI are prepared. A controllable growth of PANI nanowire arrays on the tubular MoS2 surface provides an opportunity to optimize the capacitive performance of the obtained electrodes. When the loading amount of PANI is 60%, the obtained MoS2/PANI-60 hybrid electrode not only shows a high specific capacitance of 552 F/g at a current density of 0.5 A/g, but also gives excellent rate capability of 82% from 0.5 to 30 A/g. The remarkable rate performance can be mainly attributed to the architecture with synergistic effect between 3D tubular MoS2 and PANI nanowire arrays. Moreover, the MoS2/PANI-60 based symmetric supercapacitor also exhibits the excellent rate performance and good cycling stability. The specific capacitance based on the total mass of the two electrodes is 124 F/g at a current density of 1 A/g and 79% of its initial capacitance is remained after 6000 cycles. The 3D tubular structure provides a good and favorable method for improving the capacitance retention of PANI electrode.

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In this work, functional graphene nanocomposite (reduced graphite oxidate-resol like material, named RGO-RF) was successfully synthesized and used as electrode in capacitive deionization (CDI) process. The porosity, morphology and electrochemical characteristics of RGO-RF were confirmed by N 2 adsorption-desorption curve, transmission electron microscopy and cyclic voltammetry, respectively. Further, the deionization performances of the RGO-RF electrode, reduced graphite oxidate (RGO) and activated carbon (AC) were examined for comparison by a lab-scale CDI experimental system. It is found that the RGO-RF shows the best deionization performance among the three target materials, indicating that it is a novel electrode material which has a great potential as effective electrode for CDI. Besides, the electrosorption isotherms and electrosorption kinetics were studied, and it is found that the ion sorption behaviour of RGO-RF follows a Langmuir adsorption isotherm, implying monolayer adsorption.

In aqueous zinc ion batteries (ZIBs), the H + intercalation possesses superior electrochemical kinetics with excellent rate capability, however, precisely modulating H + intercalation has been still challenging. Herein, a critical modification of pre-intercalating metal ions in the MnO 2 interlayer (MÀ MnO 2 ) with controllable pband center (ɛ p ) of O is reported to modulate the H + intercalation. The modulation of metal-O bond type and covalency degree on the average charge of O atom results in optimized ɛ p and H + adsorption energy for MÀ MnO 2 , thus promoting the balance between H + adsorption and desorption, which plays a determinant role on H + intercalation. The optimized CuÀ MnO 2 delivers superior rate capability with the capacity of 153 mAh g À 1 at a high rate of 3 A g À 1 after 1000 cycles. This work demonstrates that ɛ p could be a significant descriptor for H + intercalation, and tuning ɛ p effectively increases H + intercalation contribution with excellent rate capability in ZIBs.