Cost-effective Catalysts Research Articles

Morphology-controlled nickel-organic framework nanosheet arrays for efficient urea electrolysis in alkaline media

Urea electrolysis is considered as a promising energy-saving hydrogen production technique to substitute the water electrolysis, but it is restricted by the lack of efficient and cost-effective catalysts. Herein, nickel foam supported three-dimensional (3D) nickel-organic framework nanosheet arrays (Ni-BDC-t/NF, where t is the reaction time) comprising Ni2+ and an organic ligand of 4,4-biphenyl dicarboxylic acid (BDC) are synthesized as catalyst for urea electrolysis in alkaline media. Benefiting from the highly exposed Ni active sites and fast electron transfer rate endowed by 3D nanosheet array architecture, the structurally optimized Ni-BDC-10/NF exhibits preeminent electrocatalytic activity and durability toward urea oxidation reaction (UOR). To deliver a high current density of 100 mA cm−2, the required UOR potential of Ni-BDC-10/NF is only 1.50 V vs. RHE. Significantly, by further coupling with the cathodic hydrogen evolution reaction, the urea electrolysis system based on Ni-BDC-10/NF self-supporting anode exhibits a dramatic voltage decrease by 340 mV at a current density of 50 mA cm−2 as compared with that of water electrolysis under the same conditions. This study provides some new ideas for developing high-efficiency nickel-based organic framework catalysts and their application in urea-related energy storage devices.

La promoted Ni0-Niδ+ synergistic interaction for rapid and deep hydrogenation of liquid organic hydrogen carriers

The development of cost-effective, efficient and stable catalysts for liquid organic hydrogen carriers (LOHC) is crucial for large-scale hydrogen storage. Herein, we introduced La species into Ni/Al2O3 via co-precipitation method, yielding La-Ni/Al2O3 catalysts. Such catalysts demonstrated exceptional performance and durability in hydrogenating various LOHC candidates. Their hydrogenation capabilities surpassed most state-of-the-art and commercial catalysts, attributing to the homogenous formation of ultrafine nanoparticles induced by La species, prevention of producing unfavorable components, optimal microstructural distributions and balanced dispersion of acid sites. DFT calculations indicated that Ni-NiO(002) interface played crucial roles in modulating the electron deficiency of surface Ni atoms. The synergistic effect of Ni0-Niδ+ shifts the d-band center of Ni closer to the Fermi level, enhancing the catalyst’s adsorption capacity of intermediates and achieving higher activity toward activation of benzene and pyrrole ring, therefore leading to rapid and deep LOHC hydrogenation. The resultant catalysts exhibited great potentials for industrial applications.

Effective degradation of tetracycline in aqueous solution by an electro-Fenton process using chemically modified carbon/α-FeOOH as catalyst.

This study applied an electro-Fenton process using chemically modified activated carbon derived from rubber seed shells loaded with α-FeOOH (RSCF) as catalyst to remove tetracycline residues from aquatic environment. Catalyst characteristics were evaluated using SEM, EDS, XRD, and XPS, showing successful insertion of iron onto the activated carbon. The effects of the parameters were investigated, and the highest treatment efficiency was achieved at pH of 3, Fe: H2O2 ratio (w/w) of 500:1, catalyst dose of 1g/L, initial TCH concentration of 100mg/L, and electric current of 150mA, with more than 90% of TCH being eliminated within 30min. Furthermore, even after five cycles of use, the treatment efficiency remains above 90%. The rate constant is calculated to be 0.218min-1, with high regression coefficients (R 2 = 0.93). The activation energy (Ea) was found to be 32.2kJ/mol, indicating that the degradation of TCH was a simple reaction with a low activation energy. These findings showed that the RSCF is a highly efficient and cost-effective catalyst for TCH degradation. Moreover, the use of e-Fenton process has the advantage of high efficiency, low cost thanks to the recyclability of the catalyst, and environmental friendliness thanks to less use of H2O2.

Sustainable process intensification: Ultrasonic preparation of MIL-88A for benzoxazole synthesis

This study provides a biodegradable fumaric acid-based MIL-88A metal-organic framework, a cost-effective and non-toxic catalyst, for biologically active benzoxazoles synthesis. Initially, the ultrasonic approach is used for MIL-88A preparation at room temperature, significantly reducing the synthesis time compared to conventional heating protocols. The ultrasonic approach is once again used for the three-component production of benzoxazoles in the presence of MIL-88A catalyst. Subsequently, the benzoxazole reaction is accelerated and yields are also improved. Impressive yields ranging between 84 % and 96 % were obtained within one hour at room temperature for the three-component synthesis of benzoxazoles. Characterization techniques, including FT-IR, TEM, XRD, and SEM-EDS mapping, confirm the successful synthesis of MIL-88A. Moreover, a large-scale reaction for benzoxazole synthesis can be performed with minimal yield loss, indicating its practical application. Notably, fumaric acid, found in many fruits and vegetables, serves as the precursor for catalyst synthesis. Catechol, sourced from various plant sources, is employed for three-component production of benzoxazoles. By integrating sustainable techniques, including ultrasound-assisted synthesis and naturally available substrates, an innovative strategy was developed utilizing a renewable catalyst for an eco-friendly reaction.

Balancing the Binding of Intermediates Enhances Alkaline Hydrogen Oxidation on D-Band Center Modulated Pd Sites.

Exploring efficient alkaline hydrogen oxidation reaction (HOR) electrocatalysts is of great concern for constructing anion exchange membrane fuel cells (AEMFCs). Herein, d-band center modulated PdCo alloys with ultralow Pd content anchored onto the defective carbon support (abbreviated as PdCo/NC hereafter) are proposed as highly efficient HOR catalyst. The as-prepared catalyst exhibits exceptional HOR performance compared to the Pt/C catalyst, achieving thermodynamically spontaneous and kinetically preferential reactions. Specifically, the resultant PdCo/NC demonstrates a marked enhancement in alkaline HOR performance, with the highest mass and specific activities of 1919.6 mA mgPd-1 and 1.9 mA cm-2, 51.1 and 4.2 times higher than those of benchmark of Pt/C, along with an excellent stability in a chronoamperometry test. In the analysis of in situ Raman spectra, it was discovered that tetrahedrally coordinated H-bonded water molecules were formed during the HOR process. This indicates that the promotion of interfacial water molecule formation and enhancement of HOR activities in PdCo/NC are facilitated by defect engineering and the turning of d-band center in PdCo alloy. The essential knowledge obtained in this study could open up a new direction for modifying the electronic structure of cost-effective HOR catalysts through electronic structure engineering.

Material Engineering Strategies for Efficient Hydrogen Evolution Reaction Catalysts.

Water electrolysis, a key enabler of hydrogen energy production, presents significant potential as a strategy for achieving net-zero emissions. However, the widespread deployment of water electrolysis is currently limited by the high-cost and scarce noble metal electrocatalysts in hydrogen evolution reaction (HER). Given this challenge, design and synthesis of cost-effective and high-performance alternative catalysts have become a research focus, which necessitates insightful understandings of HER fundamentals and material engineering strategies. Distinct from typical reviews that concentrate only on the summary of recent catalyst materials, this review article shifts focus to material engineering strategies for developing efficient HER catalysts. In-depth analysis of key material design approaches for HER catalysts, such as doping, vacancy defect creation, phase engineering, and metal-support engineering, are illustrated along with typical research cases. A special emphasis is placed on designing noble metal-free catalysts with a brief discussion on recent advancements in electrocatalytic water-splitting technology. The article also delves into important descriptors, reliable evaluation parameters and characterization techniques, aiming to link the fundamental mechanisms of HER with its catalytic performance. In conclusion, it explores future trends in HER catalysts by integrating theoretical, experimental and industrial perspectives, while acknowledging the challenges that remain.

Insight of hydrogen evolution reaction in slab SnO2 loaded with transition metal atoms

The utilization of hydrogen energy has emerged as a promising solution for clean and sustainable energy sources. The development of cost-effective catalysts with high activity and stability is crucial for efficient hydrogen production. In this work, we investigated the hydrogen evolution reaction (HER) catalytic activity of single transition metal atom (TM = V, Cr, Mn, Fe, Co, Ni) on slab SnO2 by using density functional theory. Our results revealed that the catalytic activity of the slab SnO2 can be significantly enhanced by loading the transition atom. By calculating the Gibbs free energies and exchange current densities in different adsorption configurations of TM-SnO2, single-atom catalyst (SAC) of Mn-loaded SAC exhibits excellent catalytic performance, characterized by a low Gibbs free energy barrier (−0.05 eV). Introducing a TM on the SnO2 surface breaks its local symmetry, while the strong coupling between the metal and H atoms enhances catalytic performance. The synergetic effect of symmetry breaking and metal-H interaction boosts overall catalytic activity. This work not only proposes a novel non-platinum HER catalyst based on SnO2 but also lays a solid foundation for future applications of SnO2-based catalysts.

Dense heterogeneous interfaces boost the electrocatalytic oxygen evolution reaction

Efficient and cost-effective catalysts are essential to drive the oxygen evolution reaction (OER) in sustainable hydrogen production through water splitting. In this study, we introduce an innovative strategy aimed at constructing heterogeneous structure that form abundant Fe2O3/NiSe2 interfaces on the FeOOH surface. The resulting catalyst exhibits extraordinary performance with an excellently low overpotential of 169 mV at 10 mA cm−2. Notably, this catalyst also demonstrates impressive long-term stability in alkaline seawater. Compared to traditional heterogeneous catalysts with core-shell structures, Fe2O3/NiSe2 possesses a closely heterogeneous interface, which plays a role in modulating the interface electron. Supported by complementary spectroscopy and theoretical calculations, it has been further demonstrated that the distinctive Fe-O-Ni-Se structure can effectively modulate the electronic state of Ni, thereby enhancing the adsorption of oxygen-containing intermediates and facilitating oxygen desorption. Overall, this research presents a promising avenue for enhancing the electrocatalytic performance by amplifying active sites at interfaces.

Efficient ozone decomposition in high humidity environments using novel iron-doped OMS-2-loaded activated carbon material.

This study effectively addresses the rapid deactivation of manganese-based catalysts in humid environments during ozone decomposition by introducing iron-doped manganese oxide octahedral molecular sieve (Fe-OMS-2) catalysts supported on activated carbon (AC). By optimizing the doping ratio of Fe-OMS-2, the Fe-OMS-20.5/AC catalyst achieves nearly 100% ozone decomposition efficiency across a wide range of relative humidity levels (0 to 60%), even at elevated air flow rates of 800 L·g-1·h-1, outperforming standalone AC, Fe-OMS-2, or a simple mixture of OMS-2 and AC. The Fe-OMS-20.5/AC catalyst features a porous surface and a mesoporous structure, providing a substantial specific surface area that facilitates the uniform distribution of the Fe-OMS-2 active phase on the AC surface. The incorporation of Fe3+ ions enhances electron transfer between valence state transitions of Mn, thereby improving the catalyst's efficiency in ozone decomposition. Additionally, the AC component protects catalytic sites and enhances the catalyst's humidity resistance. In conclusion, this research presents a novel strategy for developing highly efficient and cost-effective ozone decomposition catalysts that enhance dehumidification, significantly contributing to industrial ozone treatment technologies and advancing environmental protection.

Self-Assembled Conjugated Coordination Polymer Nanorings: Role of Morphology and Redox Sites for the Alkaline Electrocatalytic Oxygen Evolution Reaction.

Electrocatalytic water splitting provides a sustainable method for storing intermittent energies, such as solar energy and wind, in the form of hydrogen fuel. However, the oxygen evolution reaction (OER), constituting the other half-cell reaction, is often considered the bottleneck in overall water splitting due to its slow kinetics. Therefore, it is crucial to develop efficient, cost-effective, and robust OER catalysts to enhance the water-splitting process. Transition-metal-based coordination polymers (CPs) serve as promising electrocatalysts due to their diverse chemical architectures paired with redox-active metal centers. Despite their potential, the rational use of CPs has faced obstacles including a lack of insights into their catalytic mechanisms, low conductivity, and morphology issues. Consequently, achieving success in this field requires the rational design of ligands and topological networks with the desired electronic structure. This study delves into the design and synthesis of three novel conjugated coordination polymers (CCPs) by leveraging the full conjugation of terpyridine-attached flexible tetraphenylethylene units as electron-rich linkers with various redox-active metal centers [Co(II), Ni(II), and Zn(II)]. The self-assembly process is tuned for each CCP, resulting in two distinct morphologies: nanosheets and nanorings. The electrocatalytic OER performance efficiency is then correlated with factors such as the nanostructure morphology and redox-active metal centers in alkaline electrolytes. Notably, among the three morphologies studied, nanorings for each CCP exhibit a superior OER activity. Co(II)-integrated CCPs demonstrate a higher activity between the redox-active metal centers. Specifically, the Co(II) nanoring morphology displays exceptional catalytic activity for OER, with a lower overpotential of 347 mV at a current density of 10 mA cm-2 and small Tafel slopes of 115 mV dec-1. The long-term durability is demonstrated for at least 24 h at 1.57 V vs RHE during water splitting. This is presumably the first proof that links the importance of nanostructure morphologies to redox-active metal centers in improving the OER activity, and it may have implications for other transdisciplinary energy-related applications.

Tailoring Si12C12 nanocluster with late first-row transition metals: A promising approach during single-atom catalysis toward hydrogen evolution reaction (HER)

Hydrogen evolution reaction (HER) has gained a great interest in recent years because it provides the cleanest fuel (H2). One of the most demanding things required for this reaction is an efficient and cost-effective catalyst. Single atom catalysis is one of the most remarkable strategies in this regard. Herein, transition metals adsorbed silicon carbide nanocages (TM@Si12C12; TM = Zn, Fe, Co, Cu, Ni) are investigated as single atom catalysts in order to search less expensive electrocatalysts with excellent efficiency for HER. The pure and hydrogen adsorbed TM@Si12C12 show geometric and thermodynamic stability which illustrates their practical utility. Interaction energies obtained range from −0.70 to −5.73 eV, and it is suggested that Cu@Si12C12 may play an excellent role in HER due to its lowest Gibbs free energy of −0.17 eV (near to zero). In this work, we investigated electronic properties through natural bond orbital (NBO) analysis of selected TM@SiC. According to NBO calculations, it is observed that charge is transferred from adsorbed transition metals towards nanocage. After H adsorption, NBO charge is transferred to hydrogen which shows the adsorption properties of H. In case of HOMO-LUMO energy gap, it is observed that transition metal adsorbed complexes have small energy gaps between 2.17 and 2.77 eV but after adsorption of hydrogen, this energy gap increases to lie in the range of to change from 2.93 to 3.12 eV, which also verified the electronic stability of H adsorbed species. The noncovalent interactions are estimated through NCI analysis. The density of states analysis gives insight about the energy states of occupied and unoccupied orbitals of electrons. The highest thermodynamic stability and electronic conductivity of transition metal adsorbed silicon carbide suggested it as an excellent supportive surface for HER.

The acceleration of the active phase transition of NiCoFe hydroxide by Ta doping to achieve Long-Time seawater electrolysis at Ampere-Level current density

Considering the regional distribution of freshwater resources, acquiring hydrogen by seawater electrolysis has lower cost and feasibility. NiCoFe-based materials have been widely studied due to their excellent catalytic oxidation performance in freshwater. However, the large amount of chloride ions in seawater will severely erode the catalytic site and greatly reduce the catalyst's lifetime. In this paper, a two-dimensional nanosheet quaternary metal hydroxide electrode composed of Ni, Co, Fe, and Ta elements was synthesized via a facile one-step hydrothermal method for efficient oxygen evolution reaction (OER) in seawater electrolysis. Structural characterization and in-situ test revealed that the incorporation of Ta not only optimized the electronic structure of the catalyst but also accelerated the formation of the γ-NiOOH phase, making the active phase is protected from being attacked by Cl- ions during the formation process, enhancing its OER activity while achieving extended durability. The catalyst was operated at an ampere-level of 1 A cm-2 for over one month (800 h), and no significant degradation was observed. This work provides a promising strategy for developing cost-effective, efficient, and stable catalysts for challenging applications in seawater electrolysis.

An investigation of photocatalytic and biological properties of Croton bonplandianum-mediated Ag-Cu bimetallic nanoparticles

The green synthesis of nanoparticles using plant parts and their essence is considered an archetypal tactic in material synthesis for environmental beneficence. Multitudinous metal nanoparticles with potential bioactivities have been prepared based on plant extract. This study's main objective is synthesizing Ag-Cu bimetallic nanoparticles (Ag-Cu BMNPs) using leaf extract of Croton bonplandianum L (CB). Furthermore, its photocatalytic, antibacterial, anti-fungal, and anti-tuberculosis activities are systematically investigated in detail. The surface morphology of the prepared sample is shown to be highly porous, with an average grain size of ∼ 16 nm. The FTIR spectra exhibited that the phytomolecules from CB leaf extract serve as a capping and reductantfor forming Ag-Cu BMNP. Brunauer-Emmitte-Teller (BET) comprehends the CB leaf extract to be an active, cost-effective, reusable, and high surface area catalyst. The sample exhibited improved photocatalytic activity with an efficiency of 92.31 % at the moderate catalyst dose of 30 mg against methylene blue (MB) dye. Ag-Cu BMNPs exhibited a 17 mm inhibition zone at higher concentrations against both gram (+ve) and gram (−ve) bacterial strains. Also, the synthesized Ag-Cu BMNPs produced a clear inhibition zone of 16 mm and 15 mm at lower concentrations. The anti-fungal activity against A. flavus and C. albicans at higher and lower concentrations produced a clear inhibition zone of 17 mm,15 mm, and 6 mm, 9 mm, respectively. In addition, the anti-tuberculosis activity against Mycobacteria tuberculosis exhibited good results at a 0.4 µg/mL concentration for the synthesized sample. Moreover, Ag-Cu BMNPs enhanced their biological ability and did not increase their cytotoxicity, which provides a potential for the clinical applications of Ag-Cu BMNPs. In general, the suggested method for producing Ag-Cu bimetallic nanoparticles is successful in combating microbiological diseases.

Investigation of Co3O4 modified carbon black as an efficient non-noble metal oxygen reduction catalyst in self-driven phosphorus recovery systems

Phosphorus and nitrogen recovery from urine in the form of struvite via a Mg-air fuel cell (MAFC) platform has previously been reported as a promising approach to achieving sustainable development goals. However, the applicability of this technology has been hindered by the expensive cathodic catalyst, i.e., Pt/C. In this study, an efficient and cost-effective non-precious metal catalyst, the Co3O4 doped carbon black (CB-ZIF-900), was developed to maximize nitrogen and phosphate recovery from urine while reducing investment costs. CB-ZIF-900 exhibited an oxygen reduction reaction current density of 2.95 mA cm−2 and an electron transfer number between 3.7 and 3.9 in urine solution, which approached those of commercial Pt/C at the same testing conditions. Using the MAFC, over 99 % of phosphorus was removed from urine, and >95 % of phosphorus was recovered in the precipitates. Stable phosphorus removal efficiency and precipitates composition were observed over five consecutive batch experiments. Furthermore, the MAFC with CB-ZIF-900 exhibited a maximum power density of 594.89 W m−3, surpassing that with commercial Pt/C by 9.3 %. These findings underscore the utility of the highly efficient and cost-effective CB-ZIF-900 for advancing the scalability and widespread applications of self-driven phosphorus recovery systems.

Interfaces Engineering of Ultrafine Ni@Ni2P/C Core-Shell Heterostructure for High Yield Hydrogen Peroxide Electrosynthesis.

Developing cost-effective and sustainable catalysts with exceptional activity and selectivity is essential for the practical implementation of on-site H2O2 electrosynthesis, yet it remains a formidable challenge. Metal phosphide core-shell heterostructures anchored in carbon nanosheets (denoted as Ni@Ni2P/C NSs) are designed and synthesized via carbonization and phosphidation of the 2D Ni-BDC precursor. This core-shell nanostructure provides more accessible active sites and enhanced durability, while the 2D carbon nanosheet substrate prevents heterostructure aggregation and facilitates mass transfer. Theoretical calculations further reveal that the Ni/Ni2P heterostructure-induced optimization of geometric and electronic structures enables the favored adsorption of OOH* intermediate. All these features endow the Ni@Ni2P/C NSs with remarkable performance in 2e ORR for H2O2 synthesis, achieving a top yield rate of 95.6mgL-1h-1 with both selectivity and Faradaic efficiency exceeding 90% under a wide range of applied potentials. Furthermore, when utilized as the anode of an assembled gas diffusion electrode (GDE) device, the Ni@Ni2P/C NSs achieve in situ H2O2 production with excellent long-term durability (>32h). Evidently, this work provides a unique insight into the origin of 2e ORR and proposes optimization of H2O2 production through nano-interface manipulation.

Construction of graphdiyne/CoMoO4 type II heterojunction for efficiently enhanced photocatalytic hydrogen evolution

Cost-effective bimetallic oxide catalysts are gradually replacing noble metal catalysts for photocatalytic hydrogen production. This study used a two-step method to synthesize CoMoO4 with a rod-shaped structurea. CuBr is a catalytic base synthesis graphdiyne material. The graphdiyne that serves to anchor CoMoO4 rods through a solvent-thermal synthesis method, thereby enhancing the photocatalytic performance of the resultant composite catalyst. The results show that the 5 h hydrogen evolution capacity of the optimized CoMoO4/graphdiyne composite catalyst is 187.47 μmol, which is 2.9 times higher than that of CoMoO4 monomer and 41.7 times higher than that of graphdiyne monomer. The addition of graphdiyne provides a larger comparison area for CoMoO4, giving composite catalyst more active sites, and enhancing the optical hydrogenation effect of catalysts. Through the Mott-Schottky test, the UV–visible diffuse reflectance test and band gap calculation can be speculated that the CoMoO4 and graphdiyne construct the type II heterojunction which promotes the rapid transfer of photogonic carriers. This work provides a good prospect and opportunity for studying graphdiyne in the application of graphdiyne in the application of dualmetal oxides.

Photocatalytic degradation of Acid Red 18 by synthesized AgCoFe2O4@Ch/AC: Recyclable, environmentally friendly, chemically stable, and cost-effective magnetic nano hybrid catalyst

Chitosan (Ch) is a linear biodegradable natural carbohydrate polymer and the most appealing biopolymer, such as low-cost biodegradability, biocompatibility, hydrophilicity, and non-toxicity. In this case, Ch was utilized to synthesize AgCoFe2O4@Ch/Activated Carbon (AC) by the modified microwave-assisted co-precipitation method. The physical and chemical structure of magnetic nanocomposites was analyzed and characterized by Field Emission Scanning Electron Microscope (FESEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Energy Dispersive Spectroscopy (EDS), Diffuse Reflection Spectroscopy (DRS), Value stream mapping (VSM), Fourier transform spectroscopy (FTIR) and BET. The effects of various parameters on the removal of dye (Acid Red18), including catalyst dose, dye concentration, pH, and time were studied. Results showed that the highest removal efficiencies were 96.68 % and 84 % for the synthetic sample and actual wastewater, respectively, in optimal conditions (pH: 3, the initial dye concentration: 10 mgL−1, the catalyst dose: 0.14 gL−1, time: 50 min). Mineralization, according to the COD analysis, was 89.56 %. Photocatalytic degradation kinetics of Acid Red 18 followed pseudo-first order and Langmuir-Hinshelwood with constants of kc = 0.12 mg L−1 min−1 and KL-H = 0.115 Lmg−1. Synthesized photocatalytic AgCoFe2O4@Ch/AC showed high stability and after five recycling cycles was able to remove the pollutant with an efficiency of 85.6 %. So, the synthesized heterogenous magnetic nanocatalyst AgCoFe2O4@Ch/AC was easily recycled from aqueous solutions and it can be used in the removal of dyes from industries with high efficiency.

Aminopropyl functionalized iron-phyllosilicate (AIP) engineered composite membrane for hazardous emerging pollutant treatment

Catalytic degradation of organic foulants using cost-effective and light-independent catalyst in membrane system is a promising technology in advancing the self-cleaning membranes. In this work, we report AIP-clay as an efficient light-independent catalyst in membrane system to degrade the organic foulants. The characterization of AIP-clay and membrane was performed using FE-SEM, ATR-IR, DLS, XPS, AFM, zeta potential, and contact angle measurements. The optimised AIP-clay loaded membrane (0.1AIP-PAN) showed an efficient Fenton-based insitu degradation of fouled dyes and SWW both in dark and light condition. Although, membrane exhibited significant self-cleaning capabilities in presence of light, the efficiency was nearly equivalent in dark condition as well, indicating minimal disparity in performance. The membranes remained stable even after multiple cycles of self-cleaning, with no notable loss in flux or rejection ability. The 0.1AIP-PAN membrane performance was further assessed based on the removal capacity of various salts (18% of NaCl and 38% of MgSO4), dyes (MB, MG, CR, EBT and RBr), SWW (>90%) and pharmaceuticals (>80%). In addition, the AIP-clay loaded membrane was studied for its anti-fouling property via long-term study for SWW with 97.7% FRR while retaining the membrane stability even after 216 h. Therefore, these studies demonstrate the potential self-cleaning in both dark and light, long-term stability and high separation performance of the AIP-clay membranes for diverse applications.

Innovative Application of Polyether Amine as a Recyclable Catalyst in Aerobic Thiophenol Oxidation

Polyether amines are versatile compounds characterized by a flexible structure, consisting of polyoxypropylene and polyoxyethylene as the backbone, with amine groups at each end. They have widespread applications in various industrial processes and daily life. Despite their versatility, the utilization of polyether amines as base catalysts is rare. In this study, one kind of three-arm polyether amine 1 was employed as an environmentally friendly, cost-effective catalyst for the aerobic oxidation of thiophenols, leading to the synthesis of disulfides. The oxidative coupling of thiols serves as a fundamental pathway for the production of disulfides, which are vital in both chemical and biological processes. In contrast to known methods for thiol oxidation, this polyether amine-based catalytic process eliminates the need for expensive stoichiometric oxidants and minimizes the formation of over-oxidized by-products. Using a mere 0.5 mol % of the polyether amine 1 as the catalyst, a remarkable > 96% yield was achieved for all 16 tested substrates, encompassing a diverse range of functional groups, under the catalytic aerobic oxidation conditions. Furthermore, it is noteworthy that over 90% of the polyether amine catalyst can be efficiently recovered for reuse without loss of activity, making this a sustainable and cost-effective catalytic approach.

Efficacious destruction of typical aromatic hydrocarbons over CoMn/Ni foam monolithic catalysts with boosted activity and water resistance

Developing cost-effective monolith catalyst with superior low-temperature activity is critical for oxidative efficacious removal of industrial volatile organic compounds (VOCs). However, the complexity of the industrial flue gas conditions demands the need for high moisture tolerance, which is challenging. Herein, CoMn–Metal Organic Framework (CoMn–MOF) was in situ grown on Ni foam (NiF) at room temperature to synthesize the cost-effective monolith catalyst. The optimized catalyst, Co1Mn1/NiF, exhibited excellent performance in toluene oxidation (T90 = 239 °C) due to the substitution of manganese into the cobalt lattice. This substitution weakened the Co–O bond strength, creating more oxygen vacancies and increasing the active oxygen species content. Additionally, experimentally and computationally evidence revealed that the mutual inhibiting effect of three typical aromatic hydrocarbons (benzene, toluene and m–xylene) over the Co1Mn1/NiF catalyst was attributed to the competitive adsorption occurring on the active site. Furthermore, the Co1Mn1/NiF catalyst also presents outstanding water resistance, particularly at a concentration of 3 vol%, where the activity is even enhanced. This was attributed to the lower water adsorption and dissociation energy derived from the interaction between the bimetals. Results demonstrate that the dissociation of water vapor enables more reactive oxygen species to participate in the reaction which reduces the formation of intermediates and facilitates the reaction. This investigation provides new insights into the preparation of oxygen vacancy–rich monolith catalysts with high water resistance for practical applications.