LiNiCoMnO (NCM) is regarded as a promising material for next-generation lithium ion batteries due to the high capacity, but its practical applications are limited by the poor electronic conductivity. Here, a one-step method is used to prepare carbon coated LiNiCoMnO (NCM/C) by applying active carbon as reaction matrix. TEM shows LiNiCoMnO particles are homogeneously coated by carbon with a thickness about 10 nm. NCM/C delivers the discharge capacity of 191.2 mAh g at 0.5 C (85 mA g) with a columbic efficiency of 91.1%. At 40 C (6800 mA g), the discharge capacity of NCM/C is 54.6 mAh g, whereas NCM prepared through sol-gel route only delivers 13.2 mAh g. After 100 charge and discharge cycles at 1 C (170 mA g) the capacity retention is 90.3% for NCM/C, whereas it is only 72.4% for NCM. The superior charge/discharge performance of NCM/C owes much to the carbon coating layer, which is not only helpful to increase the electronic conductivity but also contributive to inhibit the side reactions between LiNiCoMnO and the liquid electrolyte.

The efficient, green, and economical removal of radioactive iodine (I2) has drawn worldwide attention in the safe development of nuclear energy. Metal-organic frameworks (MOFs) have been demonstrated to be a...

Metal–organic frameworks (MOFs) have been demonstrated as an excellent host matrix to encapsulate diverse guest molecules for fabricating functional composite materials. Many synthetic methods have been explored to prepare white-light...

A novel two-dimensional (2D) metal−organic framework (MOF), {[Cd(hsb-2)(2-obdc)]•2H 2 O} n (HSB-W7), has been assembled from Cd(II) and the mixed ligands of hydrogenated Schiff base hsb-2 (1,2-bis(4′-pyridylmethylamino)ethane) and dicarboxylate 2-obdc (2-hydroxybenzene-1,4-dicarboxylate) via the diffusion method under mild conditions. By changing the synthetic approach with the IISEM (instant in situ exfoliation method), nanoscale MOFs (nanoMOFs) HSB-W7-Ns, HSB-W7-Ns1 and HSB-W7-NR, have also been rapidly and massively fabricated from the MOF precursors in one-pot and one-step manner under aqueous solution. These as-synthesized nanoMOFs had the same 2D crystal structure; however, they displayed diverse nanostructures from 2D rectangular nanosheets with different sizes to 1D nanorods stacked in spheres. Such morphology variations were tuned just by adjusting the initial concentration of the precursors during their nanoMOFs synthesis. Because of the exceptional water stability and strong blue fluorescence, nanoMOFs HSB-W7-Ns, HSB-W7-Ns1 and HSB-W7-NR can serve as fluorescent sensors to selectively and sensitively detect the presence of Fe 3+ ions in water. All the nanoMOFs showed much higher detection performance for Fe 3+ ions than that of their bulk MOF crystals, of which the HSB-W7-Ns MOF nanosheets with elongated rectangle morphology was the best. This work provides a new strategy for the morphology engineering of MOF nanostructures, which also offers an opportunity to improve the performance of MOFs.

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Metal–organic frameworks (MOFs) have been extensively studied in host–guest chemistry by means of ultrahigh porosities, tunable channels, and component diversities. As the host matrix, MOFs exhibit immense potential in the preparation of single-phase white light-emitting (SPWLE) materials. Nonetheless, it is a great challenge that the size of the introduced guest molecules is limited by MOF pores, which affects the WLE optimization. In this work, two-dimensional (2D) MOFs are first utilized as the host matrices to simultaneously encapsulate red–green–blue fluorescent dyes for SPWLE. Various dyes@2D MOF composites with high-quality WLE performances and ultrathin nanosheet morphologies are directly assembled from 2D MOF precursors and dyes in high yields. Owing to the flexible interlamellar space of 2D MOFs, different types and sizes of guests can be easily introduced, which greatly expands the range of available MOF hosts and guests, making the WLE much more tunable. The strategy of employing 2D MOFs as the host matrices to introduce multicomponent dyes for SPWLE nanosheets resolves the restriction of MOF pores on the guest molecule size and opens a new avenue to rationally design and prepare SPWLE nanosheets that are highly solution-processable.

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