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Catalytic performance decline is a general issue when shaping fine powder into macroscale catalysts (e.g., beads, fiber, pellets). To address this challenge, a phenolic resin-assisted strategy was proposed to prepare porous Co/N carbon beads (ZACBs) at millimeter scale via the phase inversion method followed by confined pyrolysis. Specially, p-aminophenol–formaldehyde (AF) resin-coated zeolitic imidazolate framework (ZIF-67) nanoparticles were introduced to polyacrylonitrile (PAN) solution before pyrolysis. The thermosetting of the coated AF improved the interface compatibility between the ZIF-67 and PAN matrix, inhibiting the shrinkage of ZIF-67 particles, thus significantly improving the void structure of ZIF-67 and the dispersion of active species. The obtained ZACBs exhibited a 99.9% removal rate of tetracycline (TC) within 120 min, with a rate constant of 0.069 min−1 (2.3 times of ZIF-67/PAN carbon beads). The quenching experiments and electron paramagnetic resonance (EPR) tests showed that radicals dominated the reaction. This work provides new insight into the fabrication of high-performance MOF catalysts with outstanding recycling properties, which may promote the use of MOF powder in more practical applications. [ABSTRACT FROM AUTHOR]

As the by-product of wastewater treatment, a large amount of sludge is generated annually. Turning this waste into a resource is a feasible and sustainable strategy to reduce potential environmental risks and recover energy. As a way to realize the international goal of carbon dioxide emission peak and carbon neutrality, producing biochar from sludge has gained worldwide attention. This review evaluates recent progress in synthesis techniques for biochar of sludge origin. Different preparation techniques and their key affecting factors are compared and described. The obtained sludge-derived biochar could be employed for eliminating aqueous pollution or purifying wastewater, mainly through adsorption and catalytic reactions. The removal of various pollutants by sludge-derived biochar and its related mechanisms are discussed and summarized in detail. This review will be conducive for a comprehensive understanding of recent progress in sludge-derived biochar study and for guiding the purposeful production of biochar, as well as for developing wastewater purification technology based on sludge-derived biochar. [ABSTRACT FROM AUTHOR]

Background: Long noncoding RNAs (lncRNAs) have emerged as key players in tumorigenesis and tumour progression. However, the biological functions and potential mechanisms of lncRNAs in colorectal cancer (CRC) are unclear. Methods: The novel lncRNA POU6F2-AS1 was identified through bioinformatics analysis, and its expression in CRC patients was verified via qRT–PCR and FISH. In vitro and in vivo experiments, such as BODIPY staining, Oil Red O staining, triglyceride (TAG) assays, and liquid chromatography mass spectrometry (LC-MS) were subsequently performed with CRC specimens and cells to determine the clinical significance, and functional roles of POU6F2-AS1. Biotinylated RNA pull-down, RIP, Me-RIP, ChIP, and patient-derived organoid (PDO) culture assays were performed to confirm the underlying mechanism of POU6F2-AS1. Results: The lncRNA POU6F2-AS1 is markedly upregulated in CRC and associated with adverse clinicopathological features and poor overall survival in CRC patients. Functionally, POU6F2-AS1 promotes the growth and lipogenesis of CRC cells both in vitro and in vivo. Mechanistically, METTL3-induced m6A modification is involved in the upregulation of POU6F2-AS1. Furthermore, upregulated POU6F2-AS1 could tether YBX1 to the FASN promoter to induce transcriptional activation, thus facilitating the growth and lipogenesis of CRC cells. Conclusions: Our data revealed that the upregulation of POU6F2-AS1 plays a critical role in CRC fatty acid metabolism and might provide a novel promising biomarker and therapeutic target for CRC. [ABSTRACT FROM AUTHOR]

In this work, polyacrylonitrile/aminated polymeric nanosphere (PAN/APN) nanofibers were prepared by electrospinning of monodispersed aminated polymeric nanospheres (APNs) for removal of Cr(VI) from aqueous solution. Characterization results showed that obtained PAN/APNs possessed nitrogen functionalization. Furthermore, the adsorption application results indicated that PAN/APN nanofibers exhibited a high adsorption capacity of 556 mg/g at 298 K for Cr(VI) removal. The kinetic data showed that the adsorption process fits the pseudo-second order. A thermodynamic study revealed that the adsorption of Cr(VI) was spontaneous and endothermic. The coexisting ions Na+, Ca2+, K+, Cl−, NO3− and PO43− had little influence on Cr(VI) adsorption, while SO42− in solution dramatically decreased the removal performance. In the investigation of the removal mechanism, relative results indicated that the adsorption behavior possibly involved electrostatic adsorption, redox reaction and chelation. PAN/APN nanofibers can detoxify Cr(VI) to Cr(III) and subsequently chelate Cr(III) on its surface. The unique structure and nitrogen functionalization of PAN/APN nanofibers make them novel and prospective candidates in heavy metal removal. [ABSTRACT FROM AUTHOR]

Zirconium-based metal–organic framework nanosheet assembled hydrangea-like architectures were reported and an enhanced iodine capture capacity was achieved. [ABSTRACT FROM AUTHOR]

Carbon-based electrodes play important roles in constructing efficient capacitive deionization (CDI) devices. Therefore, the rational design of carbon materials with optimized structure, composition, and morphology is crucial for further improving the CDI performance. Herein, a novel N, P co-doped eave-like hierarchical porous carbon (NP-EHPC) for CDI is reported. To prepare the NP-EHPC, the core–shell ZIF-8@AF particles are first prepared through the kinetically-controlled growth of zeolitic imidazolate framework-8 (ZIF-8) and polymerization of p-aminophenol and formaldehyde (AF), followed by subsequent pyrolysis and post-doping with phosphorus. Owing to the unique eave-like morphology, presence of abundant mesopores, and co-doping of P and N, the NP-EHPC exhibits a high desalination capacity of 24.14 mg g−1 in 500 mg L−1 NaCl solution at 1.2 V and long cycling stability of over 150 cycles. Moreover, the density functional theory (DFT) calculation results reveal that the co-doping of N and P atoms can greatly enhance the binding energies for Na and Cl atoms and lead to superior electrosorption capacity. This work provides a new insight into the design of high-performance carbon materials for the desalination of brackish water. [ABSTRACT FROM AUTHOR]

Efficient and selective removal of antibiotics from wastewater is quite important but challenging. In this work, the nitrogen-doped mesoporous carbon nanospheres (NMCN) with different pore size (from 2.67 to 4.62 nm) were successfully prepared by changing the hydrothermal condition, and their removal performance on tylosin was evaluated. The adsorption experimental data were fitted well with the pseudo-second-order kinetic model. Besides, Langmuir isotherm model could better describe the adsorption process. Notably, the NMCN with medium pore size (3.36 nm) exhibited the highest adsorption capacity (1333 mg g−1), which was 24% and 14% higher than that of NMCNs with smaller and larger pore size, respectively. In order to study the adsorption mechanism, the mesoporous carbon nanospheres without N-doped was prepared, and the comparison of nitrogen adsorption-desorption isotherms was conducted. The result proved that in addition to the modified surface property, large specific surface area, and high pore volume, the pore size could precisely influence the adsorption performance of the proposed adsorbent. Furthermore, the proposed NMCN material possessed a selective adsorbing ability toward tylosin in the presence of tetracycline. Clearly, the NMCN was a promising alternative to be used as high efficient and selective adsorbent in practical environment pollution treatment, especially in large-size molecule adsorption. [ABSTRACT FROM AUTHOR]

We introduce a viable strategy for the fabrication of core–shell ZIF-8@PVP–PDA/Zn by in situ 2-methylimidazole-assisted dopamine self-polymerization. The role of polyvinyl pyrrolidone (PVP) and 2-methylimidazole (2-MI) towards ZIF-8@PVP–PDA/Zn formation is systematically demonstrated. In particular, 2-MI not only is employed as the organic ligand for ZIF-8 but also provides an alkaline environment for the polymerization of dopamine. Moreover, it also protects the ZIF-8 structure from etching. After pyrolysis, the ZIF-8@PVP–PDA/Zn is converted into ant-nest-like hierarchical carbon (ANHC), which has a wide pore distribution, high pore volume (2.35 cm3 g−1) and high nitrogen (7.12%) content. Superior capacitive deionization (CDI) performance (25.4 mg g−1) and stable electrosorption cycles of ANHC are achieved, which demonstrates its potential for CDI applications. [ABSTRACT FROM AUTHOR]

Defect-engineered UiO-66-NH2 was introduced into a polyamide layer to form a thin film nanocomposite (TFN) membrane. Simultaneous enhancements in permeance and selectivity to Na2SO4 solution were achieved. [ABSTRACT FROM AUTHOR]

A polydopamine (PDA)-assisted interface-induction strategy is proposed to transform Zn, Co-zeolitic imidazolate frameworks (ZIFs) into hollow cactus-like carbon sheet/carbon nanotubes (CS/CNTs) for electrocatalysis for the first time. The precursor Zn, Co-ZIFs@PDA was obtained by the coordination between Co2+ (from ZIFs) and N atoms (from PDA). The introduction of PDA achieves simultaneous rational optimization of the composition (N-doping) and structure (2D/1D) by the interface-induction and confinement effect. The advantageous structure and composition endow CS/CNTs with outstanding oxygen reduction reaction activity and durability in alkaline solution. [ABSTRACT FROM AUTHOR]

A phenolic resin (PR)-assisted strategy to transform the zeolitic imidazolate framework (ZIF-67) into hierarchical Co/N-doped carbon rhombic dodecahedra for electrocatalysis is proposed for the first time. The hierarchical ZIF-67@PR composite carbon (HZPC) is obtained by coordinating the kinetic rate of precursors: nucleation/growth of ZIF-67 and polymerization of PR. The introduction of the PR polymer prevents agglomeration of cobalt nanoparticles, creates the well-distributed hierarchical porous structure and optimizes the composition. The advantages of the structure and composition endow HZPC with excellent oxygen reduction reaction (ORR) activity and long-term durability. [ABSTRACT FROM AUTHOR]

Ordered mesoporous carbon (OMC) membranes have broad applications such as size exclusion separation of molecules. In this work, a new method to prepare OMC hollow fiber membranes through a confined soft templating route is developed. In this method, commercialized polymeric hollow fiber ultrafiltration membranes were immersed in an ethanol solution containing a phenolic resin and a Pluronic triblock copolymer. Upon solvent evaporation, the phenolic resin and the surfactant self-assembled into the confined voids of the ultrafiltration membrane. After drying and pyrolysis, OMC hollow fiber membranes were obtained. The OMC hollow fiber membranes possess continuous membrane walls with an average thickness of 113 μm. The membrane wall has a hierarchical pore structure: one coming from hexagonally ordered mesoporous carbon with a pore diameter of ∼4.3 nm and the other being disordered defect holes with a size of 8–50 nm randomly distributed inside the OMC matrix. The gas permeance results indicate that the OMC hollow fiber membranes exhibit Knudsen diffusion behavior confirming their good quality. [ABSTRACT FROM AUTHOR]

Prussian blue and its analogues (PBA) based nanomaterials have been widely applied to removing pollutants in the recent years. However, easy aggregation and poor recycling largely limit their practical applications. In this work, spiderweb-like Fe-Co Prussian blue analogue/polyacrylonitrile (FCPBA/PAN) nanofibers were prepared by electrospinning and applied to degrading bisphenol-A (BPA) by activating peroxymonosulfate (PMS). Detailed characterization demonstrated that a high loading of FCPBA (86% of FCPBA in FCPBA/PAN) was successfully fixed on the PAN nanofibers. 67% of BPA was removed within 240 min when 500 mg·L−1 PMS and 233 mg·L−1 FCPBA/PAN were introduced in 20 mg·L−1 BPA solution at initial pH of 2.8. Electron paramagnetic resonance (EPR) and radical inhibition experiments were performed to identify the possible degradation mechanism. For comparison, a low loading of FCPBA nanofibers (0.6FCPBA/PAN nanofibers, 43% of FCPBA in FCPBA/PAN) were also prepared and tested the catalytic performance. The results showed that the activity of FCPBA/PAN was much higher than 0.6FCPBA/PAN. Furthermore, a FCPBA/PAN packed column was made as a reactor to demonstrate the reusability and stability of FCPBA/PAN nanofibers, which also exhibited the bright future for the industrial application. This work makes it possible to fabricate efficient PBA nanocatalysts with excellent recyclability and promotes the application of PBA in industrial areas. [ABSTRACT FROM AUTHOR]