A nickel-functionalized copper metal–organic framework (Ni@Cu-MOF) was prepared by a facile volatilization method and a post-modification synthesis method at room temperature. The obtained Ni@Cu-MOF electrode delivered a high capacitance of 526 F/g at 1 A/g and had a long-term cycling stability (80% retention after 1200 cycles at 1 A/g) in a 6 M KOH aqueous solution. Furthermore, an asymmetric supercapacitor device was assembled from this Ni@Cu-MOF and activated carbon electrodes. The fabricated supercapacitor delivered a high capacitance of 48.7 F/g at 1 A/g and a high energy density of 17.3 Wh/kg at a power density of 798.5 kW/kg. This study indicates that the Ni@Cu-MOF has great potential for supercapacitor applications.

In this study, a lanthanide metal organic framework based on the ligand of terephthalic acid derived from waste polyethylene terephthalate (PET) bottles was designed and synthesized. The structure and morphology of the Tb-BDC was investigated by X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The Tb-BDC displays a high selectivity and sensitivity towards picric acid (TNP). The luminescence intensities exhibit a linear relation, with a concentration of TNP over the range of 1 × 10⁻⁵–1 × 10⁻⁴ M, with a limit of detection of 1 × 10⁻⁵ M. The sensing mechanism is also discussed. This is the first time that waste PET materials have been used as the starting precursor of terephthalic acid (BDC) for the fabrication of lanthanide MOF (metal organic framework), which is applied in sensing TNP.

A new layer-like metal–organic framework {[Cd₄(NDIC)₄·5DMF·H₂O]DMF}_n (NDIC = 5-(5-norbonene-2,3-dicarboximide) isophthalic acid) was synthesized by solvothermal method.

Sesamol, is well-known antioxidant and can reduce the rate of oxidation and prolong expiration date. It is also potentially antimutagenic and antihepatotoxic, the detection of sesamol is important and remains a huge challenge. Herein, a new 3D alkaline earth Sr metal organic framework [Sr(BDC)DMACH₂O]n (BDC = benzene-1,4-dicarboxylate; DMAC = N,N-dimethylacetamide) is synthesized and a probe based on Tb³⁺ functionalized Sr-MOF. The Tb(3+)@Sr-MOF showed good luminescence and thermal property. Due to the energy competition between sesamol and ligand, the luminescence intensity of sesamol increases meantime luminescence intensity of Tb³⁺ decreases, the ratio of the emission intensities (I₃₄₄/I₅₄₅) linearly increases with sesamol in concentrations ranging from 1 × 10⁻⁷ to 8 × 10⁻⁴ M. Furthermore, the fluorescence-detected circular test shows that the composite Tb(3+)@Sr-MOF can serve as ratiometric sensor for sensing of sesamol. This is the first example for self-calibrated detecting sesamol based on metal-organic framework (MOF).

Core–shell structured cellulose acetate-polycaprolactone/chitosan (CA-PCL/CS) composite nanofibers were electrospun via coaxial electrospinning. Different solvents were used in core solutions, which led to different electrical conductivities in core solutions. The effect of the electrical conductivity on the morphology and structure of core–shell fibers was studied emphatically. As shown in the scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images, the increasing electrical conductivity of core solutions would result in smaller diameter ratios of core to shell, thinner overall diameters and more inhomogeneous diameter distributions. Additionally, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) all demonstrated that the interactions between cores and shells weakened with the increase of electrical conductivity of core solutions, and this might lead to different diameter ratios of cores to shells in the fibers. The results provide a basis for further design and optimization of processing conditions to control the nanostructure of core–shell composite nanofibers.

Feldspar is a high-abundance mineral in the earth’s crust, and its natural weathering and dissolution processes are an important phenomenon on the earth’s surface. This study focused on the dissolution behavior of silicon (Si) and aluminum (Al) in feldspar minerals (microcline and albite) when exposed to low-molecular-weight organic acids (LMWOAs). Various analytical techniques, including atomic absorption spectrophotometer, X-ray diffraction, scanning electron microscope, and Fourier-transform infrared spectroscopy, were employed to investigate these processes. The results revealed that the concentration of Si and Al released from alkali feldspar increased after treatment with LMWOAs, exhibiting non-stoichiometric dissolution. The Si/Al release ratio from feldspar deviated from the expected value of three. Among the LMWOAs tested, oxalic acid was found to be more effective in dissolving aluminum, while citric acid showed greater efficacy in dissolving silicon. Notably, the composite acid demonstrated the highest capacity for feldspar dissolution, with values of 538 μM (Si) and 287 µM (Al) after treatment for 720 h, respectively. The dissolution data for Si and Al in the organic acid solution was fittingly described by a first-order equation, with high correlation coefficients (R² ≥ 0.992). The characterization of feldspar powders indicated that the (040) crystal plane of feldspar was particularly susceptible to attack by organic acids. In the presence of these acids, the chemical bonds Si (Al)-O, Si-Si(Al), and O-Si(Al)-O shifted to higher wavenumbers. Additionally, the surface corrosion morphology of feldspar exhibited distinct nanostructures, which became more pronounced with increasing exposure time. It was also observed that the reactivity of feldspar increased over time. These findings provide valuable insights into the natural dissolution process of feldspar and offer a new perspective for the study of this phenomenon.