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Rechargeable aqueous zinc-ion batteries (RZIBs) provide a promising complementarity to the existing lithium-ion batteries due to their low cost, non-toxicity and intrinsic safety. However, Zn anodes suffer from zinc dendrite growth and electrolyte corrosion, resulting in poor reversibility. Here, we develop an ultrathin, fluorinated two-dimensional porous covalent organic framework (FCOF) film as a protective layer on the Zn surface. The strong interaction between fluorine (F) in FCOF and Zn reduces the surface energy of the Zn (002) crystal plane, enabling the preferred growth of (002) planes during the electrodeposition process. As a result, Zn deposits show horizontally arranged platelet morphology with (002) orientations preferred. Furthermore, F-containing nanochannels facilitate ion transport and prevent electrolyte penetration for improving corrosion resistance. The FCOF@Zn symmetric cells achieve stability for over 750 h at an ultrahigh current density of 40 mA cm−2. The high-areal-capacity full cells demonstrate hundreds of cycles under high Zn utilization conditions.

The relaxation behavior of organically modified layered silicate-epoxy nanocomposites was studied using a combination of standard and temperature-modulated differential scanning calorimetry. For such nanocomposites, the silicate layers were intercalated in the matrix resin and epoxy networks were grafted onto the silicate layer surfaces. Enthalpy recovery that occurred during physical aging was used as a probe to detect restricted relaxation behavior in the nanocomposites. Addition of the intercalated nanoparticles resulted in a slower overall relaxation rate and a wider distribution of relaxation times. The nanocomposites also showed a higher glass transition temperature compared to that of the unreinforced resin. To explain the observed results, a domain relaxation model was proposed that included three possible relaxation modes. On the basis of this model, the restricted relaxation arising from intercalated and exfoliated layered silicates can be understood.

Lithium-sulfur batteries have a poor rate performance and low cycle stability due to the shuttling loss of intermediate lithium polysulfides. To address this issue, a carbon-sulfur nanocomposite coated with reduced graphene oxide was designed to confine the polysulfides.

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We present a new type of CeO2 nanodevice in which a single CeO2 nanowire was used as the sensing unit. It was found that incorporation of Pt nanocrystals on CeO2 nanowire could significantly increase the sensor response. A possible mechanism was discussed based on the study of morphology and surface bond states of the nanowire using local electron energy loss spectroscopy and X-ray photoemission spectroscopy. The results provide a pathway to improve the performance of gas sensors with a good understanding of the nanowire’s surface physics and chemistry.