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Metal Organic Frameworks (MOFs) represent a promising class of metallic catalysts for reduction of nitrogen-containing contaminants (NCCs), such as 4-nitrophenol (4-NP). Nevertheless, most researches involving MOFs for 4-NP reduction employ noble metals in the form of fine powders, making these powdered noble metal-based MOFs impractical and inconvenient for realistic applications. Thus, it would be critical to develop non-noble-metal MOFs which can be incorporated into macroscale and porous supports for convenient applications. Herein, the present study proposes to develop a composite material which combines advantageous features of macroscale/porous supports, and nanoscale functionality of MOFs. In particular, copper foam (CF) is selected as a macroscale porous medium, which is covered by nanoflower-structured CoO to increase surfaces for growing a cobaltic MOF, ZIF-67. The resultant composite comprises of CF covered by CoO nanoflowers decorated with ZIF-67 to form a hierarchical 3D-structured catalyst, enabling this ZIF-67@Cu foam (ZIF@CF) a promising catalyst for reducing 4-NP, and other NCCs. Thus, ZIF@CF can readily reduce 4-NP to 4-AP with a significantly lower Ea of 20 kJ/mol than reported values. ZIF@CF could be reused over 10 cycles and remain highly effective for 4-NP reduction. ZIF@CF also efficiently reduces other NCCs, such as 2-nitrophenol, 3-nitrophenol, methylene blue, and methyl orange. ZIF@CF can be adopted as catalytic filters to enable filtration-type reduction of NCCs by passing NCC solutions through ZIF@CF to promptly and conveniently reduce NCCs. The versatile and advantageous catalytic activity of ZIF@CF validates that ZIF@CF is a promising and practical heterogeneous catalyst for reductive treatments of NCCs.Herein, MIL-101(Fe), CoFe2O4, novel binary (MIL-101(Fe)/CoFe2O4, MIL-101(Fe)/GO and CoFe2O4/GO), and ternary (MIL-101(Fe)/CoFe2O4/(3%)GO and MIL-101(Fe)/CoFe2O4/(7%)GO) magnetic composites based upon the MIL-101(Fe) were synthesized. The XRD, FESEM, TEM, EDX, BET-BJH, FTIR, VSM, DRS, PL, EIS and other electrochemical analyses were applied to characterize samples. The MIL/CoFe2O4/(3%)GO demonstrated the best performance compared to other samples for visible light photocatalytic and photo-Fenton-like degradation of Direct Red 23 (DtR-23), Reactive Red 198 (ReR-198) dyes as well as Tetracycline Hydrochloride (TC-H) antibiotic. Degradation of dyes using the ternary composite after 70 min of visible light irradiation was greater than that of 99%. The presence of the optimum GO as a strong electron acceptor in MIL/CoFe2O4/(3%)GO not only led to the effective separation of charge carriers and thus reduction of their recombination but also increased the absorption of visible light. The composite possessed good durability in terms of stability and reusability. The PL, EIS and electrochemical analyses indicated that the MIL/CoFe2O4/(3%)GO improved the optical properties and photocatalytic performance.The production of ammonia through electrocatalytic nitrogen reduction reaction (NRR) is environmentally friendly and energy-saving, but it still suffers from the low NH3 yield rate and poor selectivity. Herein, enlightened by the unique solubility of Fe3O4 in deep eutectic solvent (DES), we, for the first time, reported a DES-based regeneration strategy to fabricate porous Fe3O4 nanosheets utilizing commercial Fe3O4 powder as raw materials. The as-regenerated porous Fe3O4 nanosheets exhibited satisfactory electrocatalytic performance toward NRR, affording a NH3 yield rate of 12.09 μg h-1 mg-1cat along with an outstanding Faradaic efficiency (FE) of 34.38% at -0.1 V versus reversible hydrogen electrode (RHE), in the 0.1 M Na2SO4 electrolyte. The superior electrocatalytic activity of the as-regenerated Fe3O4 nanosheets mainly resulted from their unique sheet-like morphology with large active surface area, high porosity, and abundant oxygen vacancies. Our proposed DES-based regeneration strategy opens a new avenue for the construction of high-performance electrocatalyst from commercial raw materials, holding great promise in NRR.The electrochemical anodic behavior of transition metal compounds plays an undeniably non-negligible role across many electrooxidation reactions. HDAC inhibitor In this work, a chronopotentiometric technique was employed to activate the multicomponent non-noble metal oxyfluorides in-situ for oxygen evolution reaction (OER). It is interesting to unravel that the increasing applied current density helps to reconstruct the catalyst into nanoporous core-shell structure and introduce metal oxyhydroxide on the surface, which guarantees more channels for efficient ion/mass transportation and thus contributes to exposing more active sites for catalytic reaction. The activated five-membered oxyfluoride shows the best catalytic activity with overpotential of 348 ± 2 mV to achieve the current density of 10 mA/cm2 and a Tafel slope of 110.3 ± 0.1 mV/dec, in contrast with the pristine one (532 ± 2 mV & 240.2 ± 0.1 mV/dec). It still maintains high stability after long time OER measurement, making it a promising succedaneum for noble metal catalysts. The high-entropy effect, amorphous state and high active sites density jointly contribute to its enhanced OER performance. This work provides new ideas for realizing the potential of inactive elements via entropy engineering and using electrochemical self-reconstruction to modify semiconductors for advanced water oxidation.Two-dimensional (2D) coordination polymers are very interesting materials for their attractive applications. A novel 2D metal-organic framework (MOF) was derived from copper(II) and amino benzoic acid under both room temperature and solvothermal reaction conditions using different solvents. From both of the synthesis methods, an identical MOF was crystalized with monoclinic crystal system having P21/c space group. Hirshfeld surface analysis is carried out to explore the non-covalent interactions obtained from single crystal XRD investigation in terms of percentage contribution of each interatomic contact involved in packing of molecules into MOF structure. The microstructure analysis and surface morphology studies revealed the 2D layered regular pattern of rhombus disks of ~5 μm thickness throng together via clustering of these rhombic shaped flakes as flowers (ranging 50-100 μm in size) having uniform elemental composition. This 2D MOF efficiently adsorbed organic dyes (methylene blue, methyl orange, and methyl red) from their aqueous solutions. The 2D copper-carboxylate framework (1.2 g/L) exhibited high adsorption rates for organic dyes (0.15-0.19 mM), and >90% of these dyes could be captured as soon as they are exposed to MOF suspension (1 min) in each case. The dye removal efficiency is credited to synergy among structure, ionic strength, shapes and dimensions of dyes with respect to MOF structure. The microstructure of MOF along with electronic interactions like electrostatic, hydrogen bonding, π-π interactions and coordination to open metal sites, might contribute to the ultrafast dye adsorption process by MOF. The adsorption phenomenon is spontaneous and followed the pseudo-second order kinetic mechanism. DFT calculations revealed important electronic parameters of the dyes and model MOF systems, and novel insights with respect to possible dye-MOF interactions. The MOF remained quite stable during the dye adsorption and was regenerated easily for the successful subsequent use.Fe2O3/CuO p-n heterojunction photoelectrode films were fabricated by growing CuO nanoparticles on Fe2O3 nanorods via an impregnation method. The content of CuO in Fe2O3/CuO films was changed to study the role of CuO on the p-n heterojunction. The obtained Fe2O3/CuO photoelectrodes exhibited high intensity of visible-light absorption and excellence photoelectrochemical (PEC) performance. The incident photocurrent efficiency (IPCE) of Fe2O3/CuO photoanode reached 11.4% under 365 nm light irradiation, which is 2.6 times higher than that of bare Fe2O3 photoanode. In a PEC water splitting reaction, the H2 and O2 production rates for Fe2O3/CuO-3 were 0.294 and 0.130 µmol/min. The enhanced PEC performance was mainly contributed by the enhanced charge separation and the synergism achieved in Fe2O3/CuO p-n heterojunctions. This work could provide a new route to construct efficient Fe2O3-based composite photoelectrodes for the PEC.Artificial photoreduction of CO2 to chemical fuel is an intriguing and reliable strategy to tackle the issues of energy crisis and climate change simultaneously. In the present study, we rationally constructed a Ni(OH)2-modified covalent triazine-based framework (CTF-1) composites to serve as cocatalyst ensemble for superior photoreduction of CO2. In particular, the optimal Ni(OH)2-CTF-1 composites (loading ratio at 0.5 wt%) exhibited superior photocatalytic activity, which surpassed the bare CTF-1 by 33 times when irradiated by visible light. The mechanism for the enhancement was systematically investigated based on various instrumental analyses. The origin of the superior activity was attributable to the enhanced CO2 capture, more robust visible-light response, and improved charge carrier separation/transfer. This study offers an innovative pathway for the fabrication of noble-metal-free cocatalysts on CTF semiconductors and deepens the understanding of photocatalytic CO2 reduction.Vanadium oxides attract much attention and are concerned as one of the most promising cathodes for aqueous zinc-ion batteries (AZIBs) owing to the layered structures. However, their intensive development is limited by the fragile structures and laggard ion-transferring. Herein, Mn2+ inserted hydrated vanadium pentoxide nanobelts/reduced graphene oxide (MnxV2O5·nH2O/rGO, abbreviated as MnVOH/rGO) was prepared by a simple one-pot hydrothermal process, delivering excellent electrochemical properties for AZIBs. The Zn//MnVOH/rGO cell operates well even at changing current densities over 45 cycles, behaving 361 mAh·g-1 at 0.1 A·g-1, 323 mAh·g-1 as the current density gradually increasing to 2 A·g-1 and 350 mAh·g-1 when gradually back to 0.1 A·g-1 (∼97% of initial capacity). Such a superb cycling and rate performance is ascribed to the unique stable structure with the compact electrostatic attraction between Mn2+ and V2O5·nH2O (VOH) laminate. On the one hand, Mn2+ generates electrostatic network with [VO6] polyhedrons and suppresses the following electrostatic trap for the moving Zn2+. On the other hand, rGO improves the conductivity, endowing the high capacity and energy density. The performance of the MnVOH/rGO cathode exceeds most of vanadium-based cathodes applying in AZIBs and paves the way to the ideal energy storage system.

Smart membranes with robust liquid water resistance and water vapor transmission capabilities have attracted growing attentions in personal protective equipment and environmental protection. However, current fluorine-free waterproof and breathable nanofibrous membranes are usually prepared through toxic solvent-based electrospinning, which raises great concerns about their environmental impacts.

We develop environmentally friendly fluorine-free polyurethane nanofibrous membranes with robust waterproof and breathable performances via waterborne electrospinning without post-coating treatment. The incorporation of the low surface energy long-chain alkyls and polycarbodiimide crosslinker imparts the interconnective porous channels with high hydrophobicity to waterborne fluorine-free polyurethane nanofibrous membranes.

The waterborne fluorine-free nanofibrous membranes show high water contact angle of 137.1°, robust hydrostatic pressure of 35.9kPa, desirable water vapor transmission rate of 4885gm

d

, excellent air permeability of 19.

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