Industrial Chemistry & Materials最新文献

Nitrogen-rich zeolitic imidazolate frameworks (ZIFs) are ideal precursors for the synthesis of metal single atoms anchored on N-doped carbon. However, the microporous structures of conventional ZIFs lead to low mass transfer efficiency and low metal utilization of their derivatives. Here, we construct a composite of Co single atoms anchored on nitrogen-doped carbon with a three-dimensional ordered macroporous structure (Co-SA/3DOM-NC) by two-step pyrolysis of ordered macro/microporous ZnCo-ZIF. Co-SA/3DOM-NC shows high activity in the oxidative esterification of furfural, achieving a 99% yield of methyl 2-furoate under mild reaction conditions, which is significantly superior to the microporous and the Co-nanoparticle counterparts. The high activity of Co-SA/3DOM-NC should be attributed to the CoN₄ centers with high intrinsic activity and the ordered macroporous structure, promoting the mass transfer of reactants and accessibility of active sites.

Keywords: Heterogeneous catalysis; Hierarchical pores; Ordered macropore; Oxidative esterification reaction; Single-atom catalysts.

Direct regeneration is a low-cost and environmentally friendly way of recycling spent Li-ion batteries. In this study, a new method is adopted to regenerate spent LiFePO₄. First, the spent LiFePO₄ powder is homogenized, and then, small amounts of a lithium source and a carbon source are thoroughly mixed by spray drying. After that, a high-temperature solid-phase method is used to regenerate the carbon-coated lithium iron phosphate. Compared with traditional regeneration methods, the proposed method significantly improves the universality of spent LiFePO₄ having different degrees of damage. The regenerated LiFePO₄ is characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and electrochemical measurements. The results show that the regenerated sample has a stable morphology, structure, and electrochemical performance. Under the conditions of 0.1C, the initial capacity exceeds 160 mA h g⁻¹. After 800 cycles under the conditions of 1C, the capacity retention is 80%, which satisfies the requirements for regenerated LiFePO₄ batteries.

Keywords: LiFePO₄; Direct regeneration; Homogenization; Spray drying; Electrochemical performance.

In recent years, significant progress has been witnessed in organic solar cells (OSCs), which is mainly attributed to the new active layer materials design, especially fused ring acceptors. However, the majority of fused-ring acceptors suffer from complicated synthetic procedures and unsatisfactory reaction yields and thus high preparation cost. It is difficult to reconcile with the necessity for OPVs to demonstrate the low cost advantage compared with other photovoltaic technologies such as silicon or perovskite solar cells, thus significantly limiting the future application of OSCs. Therefore, it is necessary to develop high efficiency but low cost acceptor materials, i.e. non-fused ring electron acceptors (NFREAs). In this review, the recent development of NFREAs from the viewpoint of materials design is discussed. In the first and second sections, NFREAs with different central cores are reviewed. Then, the progress of fully non-fused NFREAs is summarized. Finally, an outlook on the remaining challenges to the field is provided.

Keywords: Organic solar cells; Non-fused ring acceptors; Low cost; Intramolecular noncovalent interaction; Large steric hindrance.

Heavy metal pollution is one of the most severe environmental problems, possessing high ecotoxicity and health risk. Therefore, it is important to develop effective methods and corresponding materials for the detection and removal of heavy metals. Recent studies reveal the great potential of layered double hydroxides (LDHs) in detecting and removing heavy metals owing to their designable structure and tunable surface composition. In this review, we majorly discuss the recently adopted detection and removal of heavy metal ions based on LDHs. This review starts with an introduction of the structural characteristics and functionalization of LDHs. Then, the sensing tactics and mechanisms are introduced regarding LDH-based heavy metal ion detection. Based on the type of interaction, the removal of heavy metal ions with LDHs is summarized into two categories: reversible adsorption and irreversible mineralization. This review ends with a discussion on the challenges and future trends of LDH-based detectors and adsorbents for heavy metal ions.

Keywords: Heavy metal ion; Layered doubled hydroxide; Detection; Removal.

Yolk–shell urchin-like porous Co₃O₄/NiO@C microspheres were successfully synthesized via a facile solvothermal method and annealing treatment under an argon atmosphere. High reversible specific capacity, long cycling stability, and excellent rate capability were achieved for the material due to its specific yolk–shell urchin-like porous structure and coated carbon layers. The pores distributed on the yolk and shell, as well as the gap between the yolk and shell, provide numerous pathways for the penetration of electrolyte, and enhance the reversible specific capacity (the initial discharge specific capacity was as high as 1405.7 mA h g⁻¹ at 0.1 C). Meanwhile, the stress and volume expansion could be greatly released and relieved through the pores, and long cycling stability was achieved (a high reversible specific capacity of 502.7 mA h g⁻¹ was maintained after 1000 cycles at 5 C). The coated carbon layers greatly enhance the conductivity of the yolk–shell urchin-like porous Co₃O₄/NiO microspheres, accelerate the transmission of electrons, and improve their rate performance (a reversible specific capacity of 397.5 mA h g⁻¹ was achieved when the current density was increased to 10 C).

Keywords: Yolk–shell; Urchin-like; Co₃O₄/NiO@C microspheres; Anode; Lithium storage.

Carbazole and anthracene, two aromatic hydrocarbon components contained in coal tar, are used as essential organic intermediates to synthesize various carbazole derivatives and anthraquinones. N,N-Dimethylformamide (DMF) is a commonly used solvent to extract carbazole from crude mixtures of carbazole and anthracene. However, the interaction between carbazole/anthracene and DMF in the extraction process is still to be fully understood at the molecular level. In this work, the intermolecular interaction of carbazole/anthracene with DMF was investigated using various NMR techniques, including ¹H NMR titration, variable temperature NMR spectroscopy (VT-NMR), Nuclear Overhauser Effect Spectroscopy (NOESY), and diffusion-ordered spectroscopy (DOSY). The observed ¹H chemical shift changes of carbazole indicated strong intermolecular hydrogen bonds between carbazole and DMF, which was further supported by the decrease in the molecular self-diffusion coefficients (D) of both carbazole and DMF according to DOSY measurements. Moreover, NOESY experiments revealed that the distance between the aldehydic hydrogen of DMF and the N–H of carbazole was smaller than 5 Å. Accordingly, an intermolecular hydrogen bond between carbazole and DMF in the form of CO⋯H–N was proposed. This research increases our knowledge about the separation process of carbazole and anthracene and hence helps improve the methods.

Keywords: NMR; Carbazole; Separation; Intermolecular hydrogen bonds.