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Unlike inorganic crystals, metal-organic frameworks do not have a well-developed nanostructure library, and establishing their appropriately diverse and complex architectures remains a major challenge. Here, we demonstrate a general route to control metal-organic framework structure by a solvent-assisted ligand exchange approach. Thirteen different types of metal-organic framework structures have been prepared successfully. To demonstrate a proof of concept application, we used the obtained metal-organic framework materials as precursors for synthesizing nanoporous carbons and investigated their electrochemical Na + storage properties. Due to the unique architecture, the one-dimensional nanoporous carbon derived from double-shelled ZnCo bimetallic zeolitic imidazolate framework nanotubes exhibits high specific capacity as well as superior rate capability and cycling stability. Our study offers an avenue for the controllable preparation of well-designed meta-organic framework structures and their derivatives, which would further broaden the application opportunities of metal-organic framework materials.

Owing to their nonemissive characteristics, electrochromic materials promise distinct advantages in developing next-generation eye-friendly information displays. Yet, it remains a challenge to manipulate the structure of the materials to achieve a strong memory effect with high optical contrast, which is of importance for displaying images with essentially zero energy consumption. Here, we design a mixed crystalline WO x thin film implanted with massive oxygen deficiencies based on a conventional reactive magnetron sputtering process. The obtained WO x film exhibits high dual-band optical modulation in both visible (VIS, 99.0% in 633 nm) and near-infrared (NIR, 94.2% in 1300 nm) regions as well as an exceptional memory effect (the colored transmittance increases only by 0.04% at 633 nm after 50 days). The enhanced electrochromic performance can be attributed to dense Li+-ion binding sites as well as the trapping effect provided by the massive internal oxygen deficiencies. The strategy in this work bestows the WO x thin film a promising candidate for developing electrochromic information displays and other energy-efficient devices as well.

In this work, we report a facile cryo-mediated liquid phase exfoliation method to synthesize water-soluble defect-rich MoS2 ultrathin nanosheets (d-MoS2 NSs) with the assistance of NaBH4 in the solvent. The as-prepared d-MoS2 NSs show enhanced electrocatalytic hydrogen evolution reaction (HER) performance in comparison to that of MoS2 NSs due to surface hydrophilicity and abundant active edge sites. The formation process of the d-MoS2 NSs with exposed edge sites is illustrated by investigating the influence of exfoliation time on their structural morphology. The optimal water-soluble d-MoS2 NSs display excellent HER activities, including a low overpotential of 71.5 mV at a current density of −10 mA cm–2, a small Tafel slope of 58.3 mV dec–1, and good cycling stability.

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