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In order to enhance the physical barrier performance of polyaniline(PANI)/polyurethane(PU) coating against corrosive medium, the introduction of two-dimensional material in the coating is one of the effective methods. PU coating matrix was synthesized from 2, 4-diisocyanate (TDI) and 3, 3′-dichloro-4, 4′-diamino diphenylmethane(MOCA), and MXene@PANI was synthesized by intercalation reaction of PANI with Ti3C2Tx.Then protective coating of MXene@PANI/PU was obtained by adding MXene@PANI into PU. The results show that when the mass ratio of MXene/PANI is 1∶1, no obvious corrosion occurs on the surface of the MXene@PANI/PU coating after 60 days of salt spraying. The corrosion current is 3.709×10-9 A·cm-2, and the impedance modulus is 1.93×108 Ω·cm2. The reason is that MXene improves the electrochemical activity of PANI and thus enhances the electrochemical anticorrosion performance of PANI. On the other hand, MXene nanoplates as a two-dimensional barrier can prevent the corrosive medium from entering into the coating, which improves the long-term protective performance of the coating.

For order-of-addition experiments, the response is affected by the addition order of the experimental materials. Consequently, the main interest focuses on creating a predictive model and an optimal design for optimizing the response. Van Nostrand proposed the pairwise-order (PWO) model for detecting PWO effects. Under the PWO model, the full PWO design is optimal under various criteria but is often unaffordable because of the large run size. In this paper, we consider the D-, A- and M. S. -optimal fractional PWO designs. We first present some results on information matrices. Then, a flexible and efficient algorithm is given for generating these optimal PWO designs. Numerical simulation shows that the generated design has an appealing efficiency in comparison with the full PWO design, though with only a small fraction of runs. Several comparisons with existing designs illustrate that the generated designs achieve better efficiencies, and the best PWO designs and some selected 100% efficient PWO designs generated by the new algorithm are reported. [ABSTRACT FROM AUTHOR]

Regarded as one of the popular cathode materials in aqueous zinc ion batteries (ZIBs), VS2 has unsatisfied cycling stability and relatively low capacity owing to its poor conductivity and low mechanical properties. To this regard, compositing VS2 with high‐conductive 2D transition metal carbide (MXene) has been an effective method recently. However, the Zn dendrite on the anode electrode derived from the uncontrollable sluggish migration of solvated Zn2+/H2O ions seriously threatens the application safety of ZIB batteries. To effectively regulate the diffusion of zinc ions, in this work a conductive polymeric electrolyte of sulfonated polyaniline (SPANI) is added in the electrolyte solution. Under the Zn2+/SPANI interactions confirmed by X‐ray diffraction, Raman, and zeta potential experiments, the Zn2+/H2O combination is weakened, and the deposition rate of Zn2+ is increased evaluated by the galvanostatic intermittent titration technique. Theoretical simulation shows that the electrostatic shielding by SPANI combining Zn2‐ at the zinc/electrolyte interface has important contribution to the significant suppression of Zn dendrite. Accordingly, the fabricated VS2@MXene||ZnSO4+SPANI||Zn battery shows high capacity (368.0 mAh g‐1 at 0.1 A g‐1), which remains 96% after 5000 cyclic charge–discharge operations. This work develops an available strategic idea for suppressing growth of metallic dendrites to improve the ZIB performances. [ABSTRACT FROM AUTHOR]