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[Display omitted] • Successful synthesis of Pt/Ni-MOF nanocomposite with different Pt/Ni molar ratio. • The Ni-MOF services as good supporter for the absorption of Pt nanoparticles. • Pt nanoparticles provide an abundance of active sites for methanol oxidation. • Catalyst exhibits excellent performance for MOR in acidic media. A series of Pt/Ni-MOF nanocomposites with different atom molar ratio of Pt/Ni were synthesized by the traditional hydrothermal method. Various methods including element mapping, X-ray diffraction (XRD) were employed to characterize the crystal structure and surface morphology of the materials. TEM (Transmission Electron Microscopy) confirms that the Pt nanoparticles are highly dispersed onto the Ni-MOF nanosheet surface, which can provide an abundance of active sites for efficient oxidation of methanol. Electrochemical measurements showed that Catalyst b (the atomic molar ratio of Pt to Ni is 2:1 in the precursor materials) exhibited a higher oxidation current density in MOR and larger electrochemically active surface area (ECSA) than other catalysts with different atomic ratios and commercial Pt/C. Meanwhile, the synthesized catalysts showed long-term activity and good resistance to toxicity. [ABSTRACT FROM AUTHOR]

• A "signal off" electrochemical aptasensor strategy for the detection of ENR is constructed. • AuNPs/Ni-MOF for electrode sensing platform preparation are used for catalyst thionine and signal amplification. • AuTSs acts as a bridge between cDNA and thionine, speeding up electron transfer. • The protocol possesses accepted specificity and can be applied in real sample. In this project, we developed an electrochemical aptamer sensor based on the coordinated catalysis toward thionine (Thi) of nickel metal-organic framework (Ni-MOF) and gold nanoparticles (AuNPs) to sensitively detect the enrofloxacin (ENR), which belonged to a third-generation quinolone antibiotic for treat diseases caused by bacteria. In order to improve the analytical performance of the sensor, Ni-MOF and gold AuNPs, as the substrate material, could increase the load of the aptamer (Apt) and synergistically catalyze thionine (Thi). Therefore, ultrathin sheets of gold triangular nanosheets (AuTNSs) were prepared as signal labeling materials, which were loaded with a large amount of Thi and complementary deoxyribonucleic acid (cDNA). With the help with Ni-MOF and AuNPs catalysis toward Thi, under optimal conditions, the aptasensor exhibited a massive detection range of 1×10−2 pg·mL−1 to 1×103 pg·mL−1 (S/N = 3) and a detection limit of 5.6×10−3 pg·mL−1 for ENR. Meanwhile, the proposed sensor has a high sensitivity, satisfactory repeatability and long-time stability, and could be well applied to the detection of food samples. [ABSTRACT FROM AUTHOR]

• Ni-MOF derived Ni-C composites are used as separator coating layer of Li-S battery. • The influence of different morphology Ni-C composites are compared. • Ni nanodots are proved to have catalytic effect on the conversion of polysulfides. In order to solve the problems caused by the low conductivity of sulfur and the shuttle effect of polysulfides in lithium-sulfur battery (LSB), we conducted a series of studies and successfully prepared Ni-C composite materials employing Ni-MOF as the precursor, which were used as coating materials for the separator of LSB. Two kinds of ligands, terephthalic acid and trimesic acid were used to react with nickel nitrate to obtain Ni-MOF precursors and their carbonized products were named as Ni-C(B) and Ni-C(T) respectively. Ni-MOF precursors with different morphologies were obtained by different ligands, the precursor of Ni-C(B) is the petal-like layered microspheres and the morphology maintained after calcination, the precursor of Ni-C(T) has the structure of drug flake and agglomerates into a massive structure during the reaction. Because of the uniform distribution of nickel particles and the advantages in morphology and specific surface area, the performance of batteries equipped with Ni-C(B) modified separator is better than that of Ni-C(T) sample. Through a series of electrochemical performance tests, the results are consistent with our expectations. When the sulfur area density in positive electrode is 3 mg cm−2, the highest discharge capacity of the battery using Ni-C(B) coated separator is 1413.7 mAh g−1 at 0.05C, 1169.7 mAh g−1 at 0.1C and 997.3 mAh g−1 at 0.3C. Furthermore, the initial discharge capacity is 926 mAh g−1 at 0.5 C and can retain a capacity of 600 mAh g−1 after 300 cycles. [ABSTRACT FROM AUTHOR]

Constructing a sensitive voltammetric platform to analyze highly toxic organic pollutant p-chloronitrobenzene (p-CNB) is highly desirable in environmental monitoring. Herein, a composite consisting of nickel-based metal-organic framework (Ni-MOF) and graphene oxide (GO) was successfully prepared by facile and cost-efficient chemical precipitation, and it was further used as a modified material to develop an electrochemical sensor for p-CNB. Electrochemical properties of as-prepared sensor were investigated by electrochemical impedance spectroscopy, cyclic voltammetry and differential pulse voltammetry. As a result, the composite sensor showed superior electrocatalytic performance towards the oxidation of p-CNB in a concentration range of 0.10–300.0 μM, and the detection limit was 8.0 nM (S/N = 3). Furthermore, as-prepared Ni-MOF/GO composite based sensor exhibited favorable reproducibility, durable stability and prominent selectivity. The practicability of the sensor was evaluated by detecting p-CNB in real tap water samples and satisfactory recovery rates were obtained, revealing its potential application for detection of p-CNB in water environment. Unlabelled Image • A new Ni-MOF/GO composite was successfully prepared by facile chemical precipitation. • Ni-MOF/GO/GCE exhibited prominent catalytic activity for the redox of toxic p-CNB. • Practicability of Ni-MOF/GO/GCE was evaluated via p-CNB spiked tap water samples. [ABSTRACT FROM AUTHOR]