Conductive metal–organic frameworks (c-MOFs) show great potential in electrochemical energy storage thanks to their high electrical conductivity and highly accessible surface areas. However, there are significant challenges in processing c-MOFs for practical applications. Here, we report on the fabrication of c-MOF nanolayers on cellulose nanofibers (CNFs) with formation of nanofibrillar CNF@c-MOF by interfacial synthesis, in which CNFs serve as substrates for growth of c-MOF nanolayers. The obtained hybrid nanofibers of CNF@c-MOF can be easily assembled into freestanding nanopapers, demonstrating high electrical conductivity of up to 100 S cm–1, hierarchical micromesoporosity, and excellent mechanical properties. Given these advantages, the nanopapers are tested as electrodes in a flexible and foldable supercapacitor. The high conductivity and hierarchical porous structure of the electrodes endow fast charge transfer and efficient electrolyte transport, respectively. Furthermore, the assembled supercapacitor shows extremely high cycle stability with capacitance retentions of >99% after 10000 continuous charge–discharge cycles. This work provides a pathway to develop flexible energy storage devices based on sustainable cellulose and MOFs.

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Novel nanosheets prepared by interweaving ZIF-67-templated LDH nanocrystals with nanocellulose and CNTs are applied in flexible and foldable energy storage devices.

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The cross-coupling reaction of 1,3,5-triethynylbenzene with terephthaloyl chloride gives a novel ynone-linked porous organic polymer. Tethering alkyl amine species on the polymer induces chemisorption of CO2 as revealed by the studies of ex situ infrared spectroscopy. By tuning the amine loading content on the polymer, relatively high CO2 adsorption capacities, high CO2-over-N2 selectivity, and moderate isosteric heat (Qst) of adsorption of CO2 can be achieved. Such amine-modified polymers with balanced physisorption and chemisorption of CO2 are ideal sorbents for post-combustion capture of CO2 offering both high separation and high energy efficiencies.

The organic-inorganic hybrid optical materials with a high transmittance of visible-light have shown great potential applications. However, it is still in challenge to maintain the transparency of optical materials when the inorganic nanoparticles (NPs) are introduced into the polymer matrix because of Rayleigh scattering caused by the severely aggregation of NPs, which is a huge obstacle for its applications. This article reports a transparent "solution" mixing method to fabricate a highly transparent nanocomposite film of zinc oxide (ZnO)/poly (methyl methacrylate)-co-poly (styrene) (PMMA-PS) with the novel UV-shielding properties. The transparent "solution" containing nanoparticles was prepared by phase-transfer of ZnO NPs suspension in hexane to NPs dispersion in toluene with surface modifier. The latter dispersion had the complete transparency as a solution (so-called "solution"). It was found that the incorporation of ZnO NPs not only provided UV-shielding ability to the PMMA-PS nanocomposite film with the same transparency of the pure PMMA-PS film, but also improved the thermal stability of the film. When 2% of the ZnO NPs were added into the PMMA-PS polymer, the nanocomposite film could block UV radiation at 350 nm up to 97% and allow 98% transmittance of visible light at 400 nm. The SEM and TEM studies further confirmed that the ZnO NPs were well distributed in the PMMA-PS polymer matrix with the maximum aggregated nanoparticle size less than 20 nm in diameter. High thermal stability was achieved with a 37 °C increase in the initial decomposition temperature of such nanocomposite compared to the pure PMMA-PS.

Sensitivity, line range, and response time are key indices to evaluate the performance of an electrochemical sensor. The approach commonly used to improve electrochemical performance is to search for active materials with chemical components and structures. Herein, starting with Co-based zeolitic imidazolate framework (ZIF-67), we demonstrated a sacrifice template strategy to synthesize layered double hydroxides (Co x Ni1–x -LDHs) with various microstructures and components. The structures of the obtained Co x Ni1–x -LDHs were transformed gradually from yolk–shell to hollow via regulating the molar ratio of cobalt and nickel. The yolk–shell and hollow products were composed of ZIF-67/LDHs (Co x Ni1–x -YSLDHs, x = 0.74, 0.52) and LDHs (Co x Ni1–x -HLDHs, x = 0.33, 0.21), respectively. When products were further applied to the electrochemical glucose sensor, LDHs with hollow structure have better performance than yolk–shell structure because hollow structure own a shorter electron transfer pathway than yolk–shell structure. Meanwhile, for hollow structure LDHs, Co0.33Ni0.67-HLDH exhibited relatively higher  responsive current than Co0.21Ni0.79-HLDH, probably due to its delicate structural and rational compositional merits. This work exhibits the potential of MOF derivative for designed formation of delicate structure and composition that can enhance the electrochemical performance of the sensor.