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Silicon (Si), as an ideal anode component for lithium-ion batteries, is susceptible to substantial volume changes, leading to pulverization and excessive electrolyte consumption, ultimately resulting in a rapid decline in the cycle stability. Herein, a new sodium carboxymethyl cellulose-epichlorohydrin (CMC-ECH) binder featuring a three-dimensional (3D) network cross-linked structure is synthesized by a simple ring-opening reaction, which can effectively bond the Si anode through abundant covalent and hydrogen bonds to mitigate its pulverization. Benefitting from the merits of the CMC-ECH binder, the electrochemical performance is significantly enhanced compared to the CMC binder. The CMC-ECH binder is applied to Si anodes, a specific capacity of 1054.2 mAh g–1can be maintained at 0.2 C following 200 cycles under an elevated Si mass loading of around 1.0 mg cm–2, and the corresponding capacity retention is 65.6%. In the case of the LiFePO4//Si@CMC-ECH full battery, the cycle stability exhibits a substantial enhancement compared with the LiFePO4//Si@CMC full battery. Furthermore, the CMC-ECH binder demonstrates compatibility with micron-Si anode materials. Based on the above, we have successfully developed a facilely prepared water-based CMC-ECH binder that is suitable for Si and micron-Si anodes in lithium-ion batteries.

Two reported D‐A‐D monomers based on 3,4‐ethylenedioxythiophene (EDOT) were selected for electrochemical copolymerization to obtain copolymer film, named pRG. Then, a soluble polymer poly[3,4‐ethylenedioxythiophene‐alt‐3,4‐bis([2‐ethylhexyl]oxy)thiophene] (pEA) based on the EDOT derivative was screened out, which is complementary to the absorption trough of the pRG film in visible region and matched with its working potential. The bilayer composite film pRG/pEA was obtained by spinning pEA basement membrane on fluorine doped tin oxide (FTO) coated glass surface, and then in situ electrochemical polymerization of pRG film. Compared to the pRG monolayer film, the bilayer composite film shows a more saturated black color in the neutral state and significant improvement on cyclic stability (only decreased by 1.7% after 250 cycles, while pRG film decreased by 17.1%). The introduction of pEA buffer layer not only achieves the full spectral absorption of the composite film in the visible region, but also significantly improves the cyclic stability of the bilayer composite film. The assembled EC prototype device based on the pRG/pEA composite film exhibits a “black to high transmission” reversible switch. Finally, this method combining electrochemical copolymerization, spin‐coating, lamination and other methods provides a new research idea for designing and preparing black to transmissive electrochromic materials.

A new star‐shaped structure conjugated microporous polymers, poly (2,8,14‐tri[4‐diphenyl‐benzene]‐hexaazatrinaphthylene) (PTPA‐HATN), was designed and in‐situ electrochemically polymerized on the surfaces of FTO electrodes with a directional alignment TiO2nanorod array to obtain TiO2/PTPA‐HATN core‐shell nanocomposite films. Compared with the PTPA‐HATN film, the TiO2/PTPA‐HATN composite film exhibits higher optical contrast and faster response time, with contrast of 57% at 783 nm, coloring time of 3.62 s and discoloring time of 2.55 s (43%, 4.63 s and 4.77 s for PTPA‐HATN film, respectively). After 400 cycles, the contrast of nanocomposite film decreased by 28%, while the PTPA‐HATN film basically lost its electrochromic properties. A simple three‐layer EC prototype device based on TiO2/PTPA‐HATN nanocomposite film constructed with hydrogel electrolyte clearly shows color changes at different voltages. On the one hand, the formation of core‐shell porous nanostructure of TiO2/PTPA‐HATN composite film provides a larger ion doping/de‐doping interface, shortening the average diffusion length of ions. On the other hand, the large indented polymer‐nanorods contact interface makes it difficult for the polymer to detach from the electrode, thus significantly improving the cyclic stability of the composite film.

The migration of nitroglycerin (NG) has always been the important issue on ensuring structural integrity and operational reliability of Nitrate Ester Plasticized Polyether (NEPE) propellant/Hydroxyl-terminated Polybutadiene (HTPB) liner/Ethylene Propylene Diene Monomer (EPDM) insulation bonding system. This paper designs an innovative surface modification method to prepare EPDM insulation coated with reduced graphene oxide (RGO), which weakens the NG absorption of EPDM insulation and blocks the pathway of NG migrating into EPDM insulation. The formation mechanism and microstructure of graphene-coated layer was analyzed. The RGO-coated layer is well bonded to the HTPB liner. And its anti-migration performance to NG at different temperatures was studied. Under the same storage conditions as blank samples, RGO-coated layers can reduce the diffusion coefficient of NG by the range from 82.2% to 87.3%, and increase the diffusion activation energy of NG by 26.8%. This research provides a new strategy to inhibit NG migrating in NEPE propellant/HTPB liner/EPDM insulation bonding system.