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Metal-organic frameworks (MOFs) with porous structures, high surface areas, diverse compositions, and functional linkers are promising materials and good carriers for building high-performance devices. In this work, uniform cobalt-doped ZnO nanoparticles (Co-doped ZnO NPs) derived from a MOF mold were synthesized, demonstrating the first example of synthesizing doped semiconductor metal oxide nanostructures using such strategy. The synthesis method produced Co-doped ZnO NPs that had a controllable doping mode, adjustable surface status, good dispensability, ferromagnetism and catalytic activity. The Co-doped ZnO NPs were evaluated as a sensing material for diabetes biomarker detection; the obtained sensors showed a high response to trace acetone (18.2 at 5 ppm), fast response/recovery times, a low detection limit (170 ppb), and long-term stability for 4 months. The enhanced sensing performance can be attributed to the increased number of active sites, additional impurity energy levels, and the catalytic ability of elemental Co. Moreover, the optimized sensor could distinguish between simulated diabetic breath and healthy human breath samples. The MOF-derived Co-doped ZnO NPs are a good candidate for the low-cost and noninvasive diagnosis of diabetes, and the proposed synthesis strategy can be extended to other types of extrinsically doped oxide materials., Competing Interests: Declaration of Competing Interest The authors declared that there is no conflict of interest., (Copyright © 2020. Published by Elsevier Inc.)

Graphene‐like 2D coordination polymers (GCPs) have been of central research interest in recent decades with significant impact in many fields. According to classical coordination chemistry, Cu(II) can adopt the dsp2 hybridization to form square planar coordination geometry, but not Cu(I); this is why so far, there has been few 2D layered structures synthesized from Cu(I) precursors. Herein a pair of isostructural GCPs synthesized by the coordination of benzenehexathiol (BHT) ligands with Cu(I) and Cu(II) ions, respectively, is reported. Spectroscopic characterizations indicate that Cu(I) and Cu(II) coexist with a near 1:1 ratio in both GCPs but remain indistinguishable with a fractional oxidation state of +1.5 on average, making these two GCPs a unique pair of Creutz–Taube mixed‐valence 2D structures. Based on density functional theory calculations, an intramolecular pseudo‐redox mechanism is further uncovered whereby the radicals on BHT ligands can oxidize Cu(I) or reduce Cu(II) ions upon coordination, thus producing isostructures with distinct electron configurations. For the first time, it is demonstrated that using Cu(I) or Cu(II), one can achieve 2D isostructures, indicating an unusual fact that a neutral periodic structure can host a different number of total electrons as ground states, which may open a new chapter for 2D materials. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have drawn growing attention as promising electrode candidates for rechargeable batteries. However, most studies focus on the direct use of MOF electrodes without any modification. Post‐synthetic modification, a judicious tool to modify targeted properties of MOFs, has been long‐neglected in the field of batteries. Herein, crystal‐facet engineering is proposed to design MOF‐based electrodes with high capacity and fast electrochemical kinetics. We found that a thermally‐modified strategy can regulate the dominant exposed facet of Ni‐based MOF (PFC‐8). With the optimally exposed facets, the battery exhibited admirable rate capability (139.4 mAh g−1 at 2.5 A g−1 and 110.0 mAh g−1 at 30 A g−1) and long‐term stability. Furthermore, density functional theory calculations demonstrate that stronger OH− adsorption behaviors and optimized electronic structures induced by the regulated exposed facets boost the electrochemical performance. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) heterostructures with domain‐controlled emissive colors have shown great potential for achieving high‐throughput sensing, anti‐counterfeit and information security. Here, a strategy based on steric‐hindrance effect is proposed to construct lateral lanthanide‐MOFs (Ln‐MOFs) epitaxial heterostructures, where the channel‐directed guest molecules are introduced to rebalance in‐plane and out‐of‐plane growth rates of the Ln‐MOFs microrods and eventually generate lateral MOF epitaxial heterostructures with controllable aspect ratios. A library of lateral Ln‐MOFs heterostructures are acquired through a stepwise epitaxial growth procedure, from which rational modulation of each domain with specific lanthanide doping species allows for definition of photonic barcodes in a two‐dimensional (2D) domain with remarkably enlarged encoding capacity. The results provide molecular‐level insight into the use of modulators in governing crystallite morphology for spatially assembling multifunctional heterostructures. [ABSTRACT FROM AUTHOR]

The 3d‐transition‐metal (hydro)oxides belong to a group of highly efficient, scalable and inexpensive electrocatalysts for widespread energy‐related applications that feature easily tailorable crystal and electronic structures. We propose a general strategy to further boost their electrocatalytic activities by introducing organic ligands into the framework, considering that most 3d‐metal (hydro)oxides usually exhibit quite strong binding with reaction intermediates and thus compromised activity due to the scaling relations. Involving weakly bonded ligands downshifts the d‐band center, which narrows the band gap, and optimizes the adsorption of these intermediates. For example, the activity of the oxygen evolution reaction (OER) can be greatly promoted by ≈5.7 times over a NiCo layered double hydroxide (LDH) after a terephthalic acid (TPA)‐induced conversion process, arising from the reduced energy barrier of the deprotonation of OH* to O*. Impressively, the proposed ligand‐induced conversion strategy is applicable to a series of 3d‐block metal (hydro)oxides, including NiFe2O4, NiCo2O4, and NiZn LDH, providing a general structural upgrading scheme for existing high‐performance electrocatalytic systems. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have recently emerged as appealing platforms to construct microlasers owing to their compelling characters combining the excellent stability of inorganic materials and processable characters of organic materials. However, MOF microstructures developed thus far are generally composed of multiple edge boundaries due to their crystalline nature, which consequently raises significant scattering losses that are detrimental to lasing performance. In this work, we propose a strategy to overcome the above drawback by designing spherically shaped MOFs microcavities. Such spherical MOF microstructures are constructed by amorphizing MOFs with a topological distortion network through introducing flexible building blocks into the growth environment. With an ultra‐smooth surface and excellent circular boundaries, the acquired spherical microcavities possess a Q factor as high as ≈104 and can provide sufficient feedback for high‐quality single‐mode lasing oscillations. We hope that these results will pave an avenue for the construction of new types of flexible MOF‐based photonic components. [ABSTRACT FROM AUTHOR]

• A three-dimensional inverse opal WO 3 sensor modified by MOF derived ZnO@Au nanopartilces is synthesized for H 2 S detection. • The heterojunctions, and the effective encapsulated of small sized Au NPs lead to the outstanding gas sensing performance. • The improved conductivity and the higher negative charge of O can contribute to the excellent selectivity. • The designed sensor can be applied to distinguish the abnormal H 2 S concentration in the simulated exhaled breath environment. Sensitive and selective determination of H 2 S in human exhalation is essential for understanding some physiological and pathological processes. However, effective detection of H 2 S at ppb level remains a challenge. In this work, three-dimensional inverse opal (3DIO) WO 3 structure modified with metal-organic framework (MOF) derived ZnO@Au nanoparticles (NPs) were designed and fabricated for trace H 2 S detection. The ordered macroporous structure of 3DIO, n-n heterojunctions between WO 3 and ZnO, and effective encapsulated of small-sized Au NPs benefited to the sensing performance. Compared to pristine 3DIO WO 3 sensor, the response of MOF derived 3DIO WO 3 /ZnO@Au sensor enhanced 6.5-folds (175 to 10 ppm H 2 S), the optimal working temperature dramatically decreased to 170 °C, and the actual detection limit extended to 50 ppb with a response of 8.5. The good selectivity and long-term stability of the sensor were also identified. The theoretical simulation indicated that improved conductivity, higher negative charge of O, and increased adsorption energies contributed to the excellent selectivity. Furthermore, the proposed sensor could distinguish the trace H 2 S concentration change in the exhaled breath environment. This work demonstrates an example of a simple and versatile method for high performance H 2 S gas sensor design, which is promising for exhaled breath biomarker determination. [ABSTRACT FROM AUTHOR]

[Display omitted] Protective fabrics containing Zr-Based Metal-Organic Frameworks (Zr-MOFs) show great potential in the detoxification of chemical warfare agents (CWAs). However, the current studies still face the challenges of complicated fabrication processes, limited MOF loading mass, and insufficient protection. Herein, we developed a lightweight, flexible and mechanical robust aerogel by in situ growth of UiO-66-NH 2 onto aramid nanofibers (ANFs) and assembly of UiO-66-NH 2 loaded ANFs (UiO-66-NH 2 @ANFs) into 3D hierarchically porous architecture. The UiO-66-NH 2 @ANF aerogels feature high MOF loading of 261 %, high surface area of 589.349 m2 g−1, open and interconnected cellular structure, which provide efficient transfer channels and promote catalytic degradation of CWAs. As a result, the UiO-66-NH 2 @ANF aerogels demonstrate high 2-chloroethyl ethyl thioether (CEES) removal rate at 98.9 % and a short half-life of 8.15 min. Moreover, the aerogels present good mechanical stability (recovery rate of 93.3 % after 100 cycles under 30 % strain), low thermal conductivity (λ of 25.66 mW m−1 K−1), high flame resistance (LOI of 32 %) and good wearing comfortableness, indicating promising potential in multifunctional protection against CWAs. [ABSTRACT FROM AUTHOR]

Cd-MOF was synthesized by solvothermal method. Cd-MOF has good sensitivity and selectivity for nitrofuran antibiotics (NFZ and NFT), which provides a new self-calibration method for the design and synthesis of fluorescence detection for NFZ and NFT. [Display omitted] The abuse of antibiotics has serious side effects on human health, which makes its detection particularly important. A novel three-dimensional Cd-MOF [Cd(H 2 L)(H 2 O)] n (H 2 L = 1,4-bis (2-methylimidazol-1-yl) terephthalic acid) } is successfully synthesized by solvothermal method with Cd(ClO 4) 2 ·6H 2 O and H 2 L. Further in aqueous solution using Cd-MOF as fluorescence sensor detects of nitrofuran antibiotics. The results show that the Cd-MOF can detect antibiotics with high selectivity and high sensitivity. The K sv values were calculated as 1.96 × 10-4 M−1 and 1.13 × 10-4 M−1 for nitrofurantoin (NFT) and nitrofurancillin (NFZ). The limit of detections (LODs) of Cd-MOF were 0.15 nM for NFT and 0.29 nM for NFZ. Furthermore, bimodal self-calibration detection is more accurate than unimodal detection and this research provides a reliable basis for the application of MOF in the field of fluorescence detection. [ABSTRACT FROM AUTHOR]

β-Cyclodextrin (β-CD) with a cage-like supramolecular structure possesses the hydrophobic internal ring and external hydroxyl groups, which are beneficial for intramolecular interactions known as "host-guest" chemistry. This study presents a β-CD-based three-functions-in-one and host-guest fire retardant (βCD-MOF@Schiff base), which incorporates self-crosslinking Schiff base into its cavity and modification of its surface by metal-organic framework (MOF). With the presence of 5 wt% of βCD-MOF@Schiff base, the LOI value of PLA composites increased to 29 % and showed 15 %, 17 % and 62 % reductions in peak heat release rate (pHRR), total heat release (THR), and the yield of hazard gas carbon monoxide, respectively. The mode action of FR on fire retardation of PLA showed that the FR promoted the char formation with higher thermal stability and graphitization, and modified the decomposition path of PLA. Additionally, the PLA composites exhibited enhanced UV resistance in the UVA and UVB areas with improved UV absorbance and the UPF values improving and doubling. This work develops a new approach to preparing biodegradable FR, which simultaneously endows fire safety and anti-UV properties for PLA. [Display omitted] [ABSTRACT FROM AUTHOR]

• We successfully introduce the ZIF-8 encapsulated noble metal Pt NPs into the 3DIO ZnO structure. The 3DIO Pt/ZnO materials obtained can be expanded to fabricate other kinds of small–sized and well–dispersed noble metal NPs modified 3DIO structures. • The 3DIO structure provides fast pathway for H 2 S molecules and large surface area for surface-related reactions, the Pt NPs act as high-performance catalyst. The as-prepared sensor effectively enhances the sensitivity as well as the recognition ability to trace-level H 2 S. • An optimized response of 11.2 can be achieved for 1 ppm H 2 S and a detection limit down to 25 ppb are achieved in ZIF-8 driven 3DIO Pt/ZnO sensor, which is 5.7-folds higher and 7.5 times lower than that of pristine 3DIO ZnO sensor, respectively. The effective detection of trace-level H 2 S gas is not only necessary for personal safety but is also important for understanding various physical and pathological processes in human biological systems. In this work, three-dimensional inverse opal (3DIO) ZnO sensors modified with small and well-dispersed Pt nanoparticles (NPs) are presented for ultra-low concentration H 2 S detection. The 3DIO ZnO skeleton, which is prepared through a simple self-assembly template method, provides fast diffusion pathways for H 2 S molecules and a large surface area for surface-related reactions. The optimal metal–organic framework (MOF)-derived 3DIO Pt/ZnO sensor exhibits an excellent response to trace H 2 S (11.2 at 1 ppm), a low detection limit (25 ppb), superior selectivity, and stability. The enhanced gas sensing performance can be attributed to the size effect of the Pt NPs and the rational design of the MOF-derived 3DIO Pt/ZnO nanomaterial. These results indicate that the strategy of combining the MOF-derived small and well-dispersed noble metal NPs with the 3DIO structure can efficiently improve the gas sensing properties for trace-level target gas determination. This method can likely be extended to similar systems based on 3DIO materials. [ABSTRACT FROM AUTHOR]