No abstract

Carbon nanofibers grown on the surface of graphite felt by chemical vapour deposition was investigated for the first time in vanadium redox flow batteries. The electrochemical activity and reversibility of the carbon nanofibers modified graphite felt electrode are enhanced. A catalytic mechanism for electrochemical reaction of V(IV)/V(V) couple is proposed.

No abstract

Polyaniline (PANI) is a promising cathode material for Zn-ion batteries (ZIBs) due to its intrinsic conductivity and redox activity; however, the achievements of PANI in high-performance ZIBs are largely hindered by its instability during the repeated charge/discharge. Taking advantage of the high conductivity, flexibility, and grafting ability together, a surface-engineered Ti 3 C 2 T x MXene is designed as a silver bullet to fight against the deprotonation and swelling/shrinking issues occurring in the redox process of PANI, which are the origins of its instability. Specifically, the sulfonic-group-grafted Ti 3 C 2 T x (S-Ti 3 C 2 T x ) continuously provides protons to improve the protonation degree of PANI and maintains the polymer backbone at a locally low pH, which effectively inhibits deprotonation and brings high redox activity along with good reversibility. Meanwhile, the conductive and flexible natures of S-Ti 3 C 2 T x assist the fast redox reaction of PANI and concurrently buffer its corresponding swelling/shrinking. Therefore, the S-Ti 3 C 2 T x -enhanced PANI cathode simultaneously achieves a high discharge capacity of 262 mAh g −1 at 0.5 A g −1 , a superior rate capability of 160 mAh g −1 at 15 A g −1 , and a good cyclability over 5000 cycles with 100% coulombic efficiency. This work enlightens the development of versatile MXene via surface engineering for advanced batteries.

No abstract

No abstract

The Spatial Confining Forced Network Assembly, SCFNA, is a promising method for the preparation of high performance electrical conductive polymer composites, CPCs, by constructing a forced assembly conductive network in the polymer matrix. Because the present mathematical models for predicting electrical conductivities of CPCs were derived based on the free assembly of a conductive network, they were not suitable for predicting the electrical conductivities of the CPCs by SCFNA. A mathematical model for predicting the electrical conductivities of CPCs prepared by SCFNA was proposed in this article by introducing a compression ratio based on experimental data of the CPCs of PP/CF fabricated by SCFNA. The proposed model showed a good agreement with the experimental data of electrical conductivities prepared by SCFNA method. POLYM. COMPOS., 40:1819–1827, 2019. © 2018 Society of Plastics Engineers

Liquid−liquid equilibrium (LLE) data for the ternary system 2-methyl-1-propanol + 3-methyl-1-butanol + water have been measured at (298.15, 323.15, and 348.15) K, respectively, under atmospheric pressure in this article. The Othmer−Tobias and Bachman equations were used to check the reliability of the obtained tie-line data. In addition, both NRTL (nonrandom two-liquid) and UNIQUAC (universal quasichemical) activity coefficient models were applied to the ternary system, and the relevant interaction parameters were regressed with the experimental data. The predicted values by both methods were compared with the measured experimental data. The consistency of the two models was excellent, with a better prediction by the NRTL model with a parameter α of 0.3. The obtained interaction parameters of both models can be used in the calculation of the liquid−liquid phase equilibrium of aqueous solution comprising 2-methyl-1-propanol and 3-methyl-1-butanol as well as for the design and optimization of the related separation process.