Convenient Recovery Research Articles

One-Pot Effective Approach to 2,5-Diformylfuran From Carbohydrates Using MoS2-Decorated Carbonaceous Sugarcane Bagasse.

Exploring the transformation of carbohydrates into valuable chemicals offers a promising and eco-friendly method for utilizing renewable biomass resources. Developing a bi-functional, sustainable heterogeneous catalyst is of utmost importance to attain a high level of selectivity for the desired product, 2,5-diformylfuran (DFF), in this direct conversion process. In this study, we developed a highly effective catalytic system to convert diverse carbohydrates into DFF. Our approach involved utilizing a MoS2 catalyst supported by amorphous carbon derived from sulfonated sugarcane biomass. The MoS2@SBG-SO3H composite was successfully synthesized using a facile and highly efficient method. The transformation of fructose into DFF achieved a significant yield of 70 % for 5 h at 160 °C using a one-step and one-pot reaction through dehydration and oxidation with oxygen. The oxidation of 5-hydroxymethylfurfural (HMF) into DFF using MoS2@SBG-SO3H was obtained at 94 % DFF within 5 h; the activation energy was 38.3 kJ . mol-1. The catalyst displayed convenient recovery and reusability. The direct synthesis of DFF from various carbohydrates, such as sucrose, glucose, maltose, and lactose, resulted in favorable yields. Our research provides a quick, green, and efficient process for preparing carbon-based solid acid catalysts and DFF.

Catalytic Degradation of Bisphenol A with a Magnetically Recoverable Geopolymer Composite Using Coal Gangue.

The widespread presence and use of Bisphenol A (BPA) in aquatic environments has caused significant ecological damage. Coal gangue (CG), a byproduct of coal mining, poses a major environmental concern due to its vast land occupation and potential for pollution. A magnetic recyclable geopolymer (MnFe2O4-CGP) using coal gangue geopolymer (CGP) as the carrier was successfully synthesized and was evaluated for its ability to Fenton-like degrade BPA. The characterization techniques revealed the successful incorporation of spherical MnFe2O4 onto the CGP surface and that CGP serves as an excellent platform for the immobilization and dispersion of MnFe2O4. The degradation rate reached 100% within 60 min at pH = 5, 15 mmol/L H2O2, 0.6 g/L catalyst, and 50 mg/L BPA, significantly higher than MnFe2O4 and CGP alone. It was indicated that the degradation rate of BPA in MnFe2O4-CGP composites was 0.1121 min-1, which was consistent with the first-order kinetic model. The saturation magnetization of MnFe2O4-CGP was measured to be 10.96 emu/g, enabling convenient recovery. MnFe2O4-CGP exhibited excellent stability, as the degradation rate of BPA remained above 95% even after five reaction cycles. This efficiency may be due to the MnFe2O4-CGP induced generation of reactive radicals. Quenching and EPR radical trapping experiments unequivocally confirmed that the reactive radical was hydroxyl radical (•OH). These results indicate that MnFe2O4-CGP has potential application prospects as a magnetic recyclable geopolymer composite in Fenton-like catalysis.

Citric acid steam-assisted decomposition method for the synthesis of meso-macroporous magnesium oxide with rich oxygen defects: Efficient removal and convenient recovery property of Congo red and Ni(II)

The removal of Congo red (CR) and heavy metal ion nickel (Ni(II)) from wastewater is a critical concern for safeguarding the aquatic environment and promoting sustainable development. Herein, a novel citric acid steam-assisted decomposition method is applied to form meso-macroporous magnesium oxide (MgO) with rich oxygen defects. As the gelation process of xerogel precursor could be significantly promoted by the steam-assisted process with citric acid solution as steam source, the morphology structure of MgO changes into loose aggregates with sharp edges and is covered by a layer of MgO nanoparticles. The synthesized MgO, with a high surface area (103.60 m2 g−1), meso-macroporous structure and abundant oxygen defects, exhibits super adsorption capacities for CR (7109.85 mg g−1) and Ni(II) (1405.88 mg g−1). The MgO (0.4 g L−1) could completely remove CR (200 mg L−1) in 30 min, while 10 min for Ni(II) (200 mg L−1) adsorption. The adsorption mechanism of MgO for CR and Ni(II), including electrostatic interaction, oxygen vacancy capture, hydrogen bonding and ion exchange, is effectively enhanced due to the appearance of meso-macroporous structure and oxide defects, such as 5-coordinated oxygen anion (O5C2−) for terrace, 4-coordinated oxygen anion (O4C2−) for edge and 3-coordinated oxygen anion (O3C2−) for corner. The easy calcination is applied to recycle MgO after CR adsorption and the CR removal efficiencies are above 98 % after five cycles. Meanwhile, a nickel chelator (Na2EDTA) and calcination are used to regenerate the MgO after Ni(II) adsorption and the adsorbent shows an insignificant removal efficiency loss after three cycles. The meso-macroporous MgO with rich oxygen defects has the characteristics of high adsorption speed, high adsorption capacity and convenient recovery property, and is expected to become an ideal material for the rapid treatment of high concentration wastewater.

Rapid degradation of formaldehyde using Fe coupled with walnut shell biochar with high surface defect in Fenton-like reaction

The Fenton technology used for treating formaldehyde-containing wastewater (HCHO) has limitations in terms of pH, efficiency, and cost. To address these issues, a Fex-HT Fenton-like catalyst was developed in this study. This catalyst combines active Fe with walnut shell biochar (HT) that contains surface defects, resulting in a highly effective solution for the rapid purification of formaldehyde wastewater in complex environments. The carbon defects on the HT surface play a crucial role in stabilizing the active Fe binding, while the appropriate loading of Fe further enhances the specific surface area of HT. Additionally, the porous structure of HT provides ample contact sites for formaldehyde. Furthermore, the Fe3-HT catalyst exhibits superparamagnetism, allowing for convenient recovery of the catalyst after use. Experimental results demonstrate that Fe3-HT achieves an impressive 90% degradation rate for systems containing HCHO concentrations ranging from 200 to 800 mg/L. The effects of feed ratio, pH, and formaldehyde concentration on the performance of Fe3-HT were thoroughly investigated. Moreover, a possible mechanism for the degradation of HCHO by the Fe3-HT Fenton-like catalyst was proposed. The environmentally friendly catalyst developed in this study boasts numerous advantages, including low cost, high treatment capacity for wastewater, and strong adaptability to complex wastewater environments.

Photovoltaic high-throughput microfluidic platform for the mass-production of hybrid viscous microdroplets towards diverse applications

Scientists have been pursuing a compact, electrodeless microfluidic platform with a simple structure to realize the efficient cascading manipulations of serial aqueous microdroplets. In this study, we present a photovoltaic microfluidic platform to handle viscous Sodium-Alginate-doped aqueous microdroplets dispersed in a continuous surfactant-doped oil phase. Three kinds of optical response (Non-coalescence, Successful coalescence, and Bouncing back) are observed between adjacent microdroplets. Both the surfactant and SA concentrations are employed to optimize the laser-illumination intensity range of successful coalescence. We realized, that by simply applying focused-laser illumination, the sequential cascading of microfluidic manipulations including trapping, coalescence, mixing, and release of viscous aqueous microdroplets could be controlled in a reconfigurable, high-throughput manner. By properly adjusting the laser-illumination intensity, we can control the number of the microdroplets participating in the coalescence as well as the degree of the liquid mixing inside coalescent microdroplets, thus realizing the mass-production of hybrid viscous aqueous microdroplets. With this platform, we prepare Janus microparticles possessing magnetic and phosphorescent properties for assembling a magnetically driven displayer. Moreover, bioreactors are prepared with both immobilized yeast cells for effective fermentation and embedded magnetic nanoparticles for convenient recovery. Additionally, we generate, on this platform, chains of fluorescent double-emulsion microdroplets for optically encoding the information of the target microdroplet. The photovoltaic MHTE platform, with a simple chip design and good integrability with other LN-based photonic components, allows for an electrodeless, biocompatible manipulation of serial aqueous microdroplets with minimal temperature fluctuation, showing great potential in diverse fields including optics, MEMS, biotechnology and chemical sciences.

A noval salt effect coupled vacuum distillation process for high efficient ultra-azeotropic reuse of spent HCl

The escalating challenge of recycling and treating spent hydrochloric acid (HCl) in various industries, driven by stringent environmental regulations, necessitates urgent solutions for the reuse of spent HCl in industrial processes. However, the concentration and reuse of spent HCl have been impeded by azeotropism. In this study, an innovative salt effect coupled vacuum distillation process was introduced to enable the rapid and convenient recovery of HCl. Salts and vacuum environment both can be found to break the azeotropism effectively, augment the disparity in the dissociation abilities of HCl and H2O in clusters, and enhance the evaporation rate. Specifically, MgCl2 and CaCl2 salt systems were selected, achieving recovered HCl concentrations of 9.66 and 9.85 mol/L, with corresponding recovery rates of 86.45 % and 80.65 %, respectively. For the reuse of spent HCl from chlorinated distillation for extracting germanium (Ge), the presence of As(V) poses a risk to Ge recovery and potential contamination of the Ge product. Excellent resistance to As(Ⅴ) mobilization (<2%) was obtained in the CaCl2 system. To comprehensively understand the salt’s role in breaking azeotropism, molecular simulations were employed. The Mg2+/Ca2+ ions were observed to bind with H2O molecules in the solution, weakening the force between H2O and HCl, decreasing the dissociation energy of HCl molecules by 35 times (from 102.82 to 2.94 kJ/mol), and increasing the dissociation energy of H2O molecules from 52.5 to 61.5 kJ/mol. The proposed process integrates high HCl recovery with an ultra-azeotropic concentrating effect, offering a novel approach for reusing spent HCl in industrial applications.

Synthesis of a composite Fe3O4@SiO2/poly(SMA-co-BA-co-BZMA-co-DMC) and evaluation of its oil-water separation performance

To obtain a demulsification material with convenient recovery, high oil-water separation capacity, and excellent reusability, Fe3O4@SiO2 core-shell particles and hydrophilic DMC were introduced into the acrylic ester-based polymer system to prepare a magnetic amphiphilic composite demulsifier, Fe3O4@SiO2/poly(SMA-co-BA-co-BZMA-co-DMC) (Fe3O4@SiO2/PAMCs-P). The molecular structure of Fe3O4@SiO2/PAMCs-P was characterized using FT-IR and XPS, while the morphology was observed using SEM. Additionally, the effects of TEOS, Fe3O4@SiO2 core-shell particles, and DMC dosage on the demulsification performance of the composites were discussed in detail. Fe3O4@SiO2/PAMCs-P exhibited excellent demulsification, oil-water separation, and reusability properties for CTAB-toluene emulsions. Under magnetic field conditions, Fe3O4@SiO2/PAMCs-P achieved saturated separation within 2 h with a separation efficiency of 97.9%. After five consecutive separations, the separation efficiency decreased to 39.1%, but it could be restored to 91.5% of the initial separation efficiency after desorption. These results indicate that Fe3O4@SiO2/PAMCs-P has valuable application potential in emulsified wastewater treatment.

Efficient synthesis of novel thiadiazolo[2,3-b]quinazolin-6-ones catalyzed by diphenhydramine hydrochloride-CoCl2⋅6H2O deep eutectic solvent

In this research, a new Lewis acid-based deep eutectic solvent (LA-DES) was synthesized using diphenhydramine hydrochloride and CoCl2·6H2O, (2[HDPH]:CoCl42−), and identified by FT-IR and 1HNMR techniques. The physicochemical properties of this LA-DES, such as thermal behavior, thermal stability, and solubility in common solvents were also investigated. The catalytic ability of 2[HDPH]:CoCl42− was ascertained in the efficient synthesis of a novel array of thiadiazolo[2,3-b]quinazolin-6-one scaffolds via a one-pot three-component reaction of dimedone/1,3-cyclohexanedione, aldehydes, and 5-aryl-1,3,4-thiadiazol-2-amines/3-(5-amino-1,3,4-thiadiazol-2-yl)-2H-chromen-2-one under solvent-free conditions. This catalyst was also successfully utilized for the synthesis of mono- and bis-thiadiazolo[2,3-b]quinazolin-6-ones from dialdehydes or bis-1,3,4-thiadiazol-2-amine. The simplicity of enforcement, short reaction time, avoidance of toxic organic solvents, scalability of the synthesis procedure, excellent atom economy, high reaction mass efficiency, and low E-factor are other outstanding advantages of this newly developed method. Furthermore, due to the convenient recovery and reuse of LA-DES, this protocol is economically justified and environmentally friendly.

Tuning the heterostructure of Zn–Fe–O nanoparticles for highly efficient photocatalytic removal of U(vi) under different light intensities

Fe2O3 has received a lot of attention due to its low cost, easy doping regulation, and convenient recovery.

Improving sustainability of cellulose nanofibrils production: FTIR spectroscopy for online control of the synthesis of recyclable magnetic TEMPO catalyst

2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) and its derivatives are well-established catalysts for various oxidation processes, despite its hazardous nature, causing harm to aquatic ecosystems. Thus, the reuse of TEMPO with a sustained high activity has gained significant importance for its industrial application, which has led to the development of supported TEMPO catalyst. In this context, the efficiency of the support process acquires high relevance. Therefore, this research is aimed at the improvement of the TEMPO supported on silica magnetically modified with Fe3O4 through the application of an online Fourier transform infrared spectroscopy (FTIR) probe to monitor its synthesis. FTIR effectively controlled the synthesis of supported TEMPO, by tracking online the concentration of 3-aminopropyltriethoxysilane (APTES) and tetraethyl orthosilicate (TEOS). Additionally, the presence of Fe3O4 particles in the core of the catalyst allowed its convenient recovery and subsequent reuse. Furthermore, the supported TEMPO catalyst was successfully applied in the oxidation of cellulose to produce nano/microfibrils. The carboxyl groups of the initial untreated cellulose increase from 0.05 mmol/g to 0.68 mmol/g with the supported TEMPO catalyst in presence of sodium hypochlorite and sodium bromide at 50 °C.

Synthesis of ferromagnetic 3DOM MgO/MgFe2O4 with superb adsorption capacity and convenient recovery properties for efficient capture of La(Ⅲ) and Ce(Ⅲ) from wastewater

The mining of ion-adsorption rare earth minerals or ores generated a large amount of wastewater containing rare earth elements at low-concentration, resulting in continuous environmental pollution. For this problem, our study prepared an efficient, recyclable MgO/MgFe2O4 magnetic adsorbent, synthesized by a template method and characterized using XRD, SEM-EDS, BET, and VSM. The isothermal adsorption experiments and adsorption kinetic experiments were carried out to evaluate the ability of MgO/MgFe2O4 to remove La(Ⅲ) and Ce(Ⅲ), and the effects of the initial pH of the solution and the dosage were also investigated. FT-IR and XPS analyzed the ion-exchange mechanism between La(III) and Ce(III) ions and the hydroxyl functional groups present in the adsorbent, culminating in the formation of La/Ce-OH complexes. MgO/MgFe2O4 demonstrated a theoretical adsorption capacity of 2002 mg/g and 5317 mg/g for La(III) and Ce(III), respectively, achieving removal rates of 97.2% and 98.7% in dilute solutions, marking it as a potent solution for rare earth element remediation in wastewater. This advancement holds substantial implications for environmental management within rare earth mining locales.

Facile preparation of metal-organic framework beads for effective capture of indium ion

The adsorption and recovery of indium (In) ions from water is necessary while still faces challenges. Current adsorbents for this valuable metal commonly show powder states, which easily results in mass loss and goes against their convenient recovery. In this work, the nanoscale metal-organic framework UiO-66-(COOH)2 particles were successfully embedded in sodium alginate (SA)-calcium structure, to fabricate UiO-66-(COOH)2/SA composite beads. The beads show a homogenous size of ∼3 mm, cellular-like interior structure, and high MOF loading amount (70.4 wt%). Besides, their high water stability and anti-pressure property were proved. UiO-66-(COOH)2/SA beads exhibit a large adsorption amount for In3+ ions (81.2 mg g−1) and rapid adsorption equilibrium time (∼5 min) at low concentrations. Importantly, it is found that In3+ ions can diffuse into the interior frameworks of the beads via the transparent transmission channels. The optimal pH for adsorption locates at 4.0 and temperature may have only a slight effect. Furthermore, the beads can be regenerated based on a simple solvent elution method. The mechanism analysis confirms that the C–O–C and C–OH (or –COOH) groups from both SA and MOF contents contribute to the adsorption. So, our work provides an effective bead-state adsorbent for In3+ ions.

Optimization of Visible-Light-Driven Ciprofloxacin Degradation Using a Z-Scheme Semiconductor MgFe2O4/UiO-67.

A heterogeneous photocatalyst, MgFe2O4/UiO-67 (MU-x), was successfully synthesized by doping magnetic magnesium ferrite nanoparticles (MgFe2O4) with the UiO-67 metal-organic framework at various weight ratios (MgFe2O4: UiO-67 at 30, 50, 70, and 90 wt %). Various techniques, including X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR) , Brunauer-Emmett-Teller (BET), photoluminescence (PL), vibrating sample magnetometry (VSM), electrochemical impedance spectroscopy (EIS), and ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS), were used to characterize the prepared photocatalysts. The photocatalytic performance of MU-x in the degradation of ciprofloxacin (CIP) under visible light was assessed. The CIP degradation efficiency was found to increase as the amount of MgFe2O4 in the composite was increased up to 70 wt %. Experimental conditions were optimized using response surface methodology (RSM) based on central composite design (CCD) with three factors: initial pH, catalyst loading, and CIP concentration. Using the obtained model, the optimal conditions were determined as follows: initial pH of 8.025, catalyst loading of 33.8 wt %, and CIP concentration of 10.8 mg/L. Under these optimal conditions, a notable improvement was achieved, with 99.62% of CIP removal achieved within 90 min, surpassing the performance of previously reported photocatalysts. Total organic carbon (TOC) analysis revealed a high degree of mineralization, at 81.25%. The degradation pathway of CIP was investigated based on liquid chromatography-mass spectrometry (LC-MS) analysis. Finally, the values of ECB and EVB of the photocatalyst were determined and the possible degradation mechanism of CIP was investigated based on Mott-Schottky and the applied scavengers. The hydroxyl radical (•OH) was identified as the dominant species in the removal of CIP through a trapping experiment. The photocatalyst with 70 wt % of MgFe2O4 (MU-70) exhibited excellent stability and recoverability with an external magnet, demonstrating 86.33% CIP removal after four cycles. According to the obtained results, MU-70 is a promising visible-light-active photocatalyst with great potential for water treatment applications and convenient recovery.

Magnetic Carbon Quantum Dots/Iron Oxide Composite Based on Waste Rice Noodle and Iron Oxide Scale: Preparation and Photocatalytic Capability.

To provide an economical magnetic photocatalyst and introduce an innovative approach for efficiently utilizing discarded waste rice noodle (WRN) and iron oxide scale (IOS), we initially converted WRN into carbon quantum dots (CQDs) using a hydrothermal method, simultaneously calcining IOS to obtain iron oxide (FeOx). Subsequently, we successfully synthesized a cost-effective, magnetic CQDs/FeOx photocatalytic composite for the first time by combining the resulting CQDs and FeOx. Our findings demonstrated that calcining IOS in an air atmosphere enhanced the content of photocatalytically active α-Fe2O3, while incorporating WRN-based CQDs into FeOx improved the electron-hole pair separation, resulting in increased O2 reduction and H2O oxidation. Under optimized conditions (IOS calcination temperature: 300 °C; carbon loading: 11 wt%), the CQDs/FeOx composite, utilizing WRN and IOS as its foundation, exhibited exceptional and reusable capabilities in photodegrading methylene blue and tetracycline. Remarkably, for methylene blue, it achieved an impressive degradation rate of 99.30% within 480 min, accompanied by a high degradation rate constant of 5.26 × 10-3 min-1. This composite demonstrated reusability potential for up to ten photocatalytic cycles without a significant reduction in the degradation efficiency, surpassing the performance of IOS and FeOx without CQDs. Notably, the composite exhibited strong magnetism with a saturation magnetization strength of 34.7 emu/g, which enables efficient and convenient recovery in photocatalytic applications. This characteristic is highly advantageous for the large-scale industrial utilization of photocatalytic water purification.

Synthesis and Characterization of Novel Magnetic Nano-Biocomposite Hydrogels Based on Starch-g-poly(acrylic acid) Reinforced by Cellulose Nanofibers for Cu2+ Ion Removal.

One of the crucial challenges of the adsorption process is to recapture the adsorbent from the solution, especially for adsorbents in powder form. This study synthesized a novel magnetic nano-biocomposite hydrogel adsorbent to successfully remove Cu2+ ions, followed by convenient recovery and reusability of the adsorbent. The Cu2+ adsorption capacity of starch-g-poly(acrylic acid)/cellulose nanofibers (St-g-PAA/CNFs) composite hydrogel and magnetic composite hydrogel (M-St-g-PAA/CNFs) was investigated and compared in both bulk and powder forms. Results showed that Cu2+ removal kinetics and swelling rate were improved by grinding the bulk hydrogel into powder form. The kinetic data and adsorption isotherm were best correlated with the pseudo-second-order and Langmuir models, respectively. The maximum monolayer adsorption capacity values of M-St-g-PAA/CNFs hydrogels loaded with 2 and 8 wt % Fe3O4 nanoparticles in 600 mg/L Cu2+ solution were found to be 333.33 and 555.56 mg/g, respectively, compared to 322.58 mg/g for the St-g-PAA/CNFs hydrogel. Vibrating sample magnetometry (VSM) results demonstrate that the magnetic hydrogel that included 2 and 8 wt % magnetic nanoparticles exhibited paramagnetic behavior with the magnetization of 0.6-0.66 and 1-1.04 emu/g at the plateau, respectively, which showed a proper magnetic property and good magnetic attraction in the magnetic field for separating the adsorbent from the solution. Also, the synthesized compounds were characterized by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and Fourier transform infrared spectroscopy (FTIR). Finally, the magnetic bioadsorbent was successfully regenerated and reused for four treatment cycles.

Faster Riemannian Newton-type optimization by subsampling and cubic regularization

This work is on constrained large-scale non-convex optimization where the constraint set implies a manifold structure. Solving such problems is important in a multitude of fundamental machine learning tasks. Recent advances on Riemannian optimization have enabled the convenient recovery of solutions by adapting unconstrained optimization algorithms over manifolds. However, it remains challenging to scale up and meanwhile maintain stable convergence rates and handle saddle points. We propose a new second-order Riemannian optimization algorithm, aiming at improving convergence rate and reducing computational cost. It enhances the Riemannian trust-region algorithm that explores curvature information to escape saddle points through a mixture of subsampling and cubic regularization techniques. We conduct rigorous analysis to study the convergence behavior of the proposed algorithm. We also perform extensive experiments to evaluate it based on two general machine learning tasks using multiple datasets. The proposed algorithm exhibits improved computational speed, e.g., a speed improvement from 12% :text {to} :227%, and improved convergence behavior, e.g., an iteration number reduction from mathcal{O}left(maxleft(epsilon_g^{-2}epsilon_H^{-1},epsilon_H^{-3}right)right) ,text {to}: mathcal{O}left(maxleft(epsilon_g^{-2},epsilon_H^{-3}right)right), compared to a large set of state-of-the-art Riemannian optimization algorithms.

Green iron oxide-modified biochar for methylene blue removal from aqueous solutions

Textile industrial wastewater, a major source of effluent coloration, has been identified as a threat to human and animal health. A difficult and significant challenge is the complete removal of poorly biodegradable dyestuffs from complex environmental matrices. We synthesized a green iron oxide-loaded Douglas fir biochar (FDBC) hybrid using commercially available biochar, DBC, to effectively remove aqueous methylene blue (MB). Both modified and pristine adsorbents are microporous, and their MB removal speeds are very high (equilibrate in 5 min) at an initial MB concentration of 25 ppm. Large surface areas (640 m2/g versus 248 m2/g) and pore volumes (0.13 cm3/g versus 0.07 cm3/g) of DBC and FDBC partially facilitate MB surface physisorption. Compared to DBC, the maximum Langmuir adsorption capacity of FDBC is higher (634.0 mg/g versus 740.5 mg/g), indicating the hybrid adsorbent design that involves the iron oxide phase plus the biochar backbone (1500 ppm initial [MB], t = 5 min, and pH 6.8). The addition of Fe3O4 nanoparticles (∼11.0 nm) promotes the adsorption of MB on FDBC (due to the increase in the surface Fe3O4 concentration), while allowing small adsorbent particles of spent FDBC to be easily removed from batch treatments using a magnet. The magnetic variant (FDBC) simultaneously adsorbs three co-existing BP, BG, and MB with over ∼90% efficiency. Spent FDBC could be regenerated easily by stirring in Methanol. FDBC would be more economical in terms of its facile synthesis, efficient and fast MB adsorption, convenient recovery, pH-independent MB uptake, and treatment of variety of wastewaters etc.

Sulfur self-doped g-C3N4 nanofiber modified by NiO co-catalyst: An efficient, collectible, durable, and low-cost photocatalyst for visible-light-driven hydrogen evolution from water

The energy dilemma is exacerbating. Artificial photosynthesis is a plausible blueprint for solar-to-fuel conversion applications to satisfy future energy demands. Developing a cheap, efficient photocatalyst material can be the watershed moment in this field. Herein, low-cost sulfur self-doped g-C3N4 nanofiber decorated by nickel oxide (denoted as x%NiO/S-g-C3N4-F) was obtained via electrospinning and one-step thermal treatment (575 °C). Outstandingly, the modified g-C3N4-based material could interact and harvest long wavelengths up to 706 nm. Moreover, the quantified specific surface area (SSA) for 2%NiO/S-g-C3N4-F is more than 17.3 folds larger than S self-doped g-C3N4 bulk (denoted as S-g-C3N4 bulk). As a result, the optimal photocatalytic property of 2%NiO/S-g-C3N4-F is almost five times as high as S-g-C3N4 bulk, achieving 107.04 μmol/h. The suggested photocatalysis mechanism was proposed and supported by the results. Significantly, loading a proper amount of NiO over modified S-g-C3N4 promoted performance as well as convenient recovery and reusability. According to the experimental and characterization results, the fabricated 2%NiO/S-g-C3N4-F consider a potential candidate for photocatalytic applications, especially Vis-light-driven H2 evolution.

Surface magnetized MgAl-LDHs and MgAl-LDO with excellent adsorption capacity and convenient recovery for the removal of U(VI)

Surface magnetized MgAl-LDHs and MgAl-LDO with excellent adsorption capacity and convenient recovery for the removal of U(VI)

Dual mode fluorometric and colorimetric detection of matrix metalloproteinase MMP-9 as a cancer biomarker based on AuNPs@gelatin/AuNCs nanocomposite

Matrix metalloproteinase (MMPs) are proteolytic enzymes which considered as important enzymes and their higher expression is associated with some malignant progression. In the present study, a novel and sensitive method was developed for detection of MMP-9 based on its gelatinase activity. Green emitting gold nanoclusters (AuNCs) has been synthesized by gelatin substrate and then AuNPs@gelatin/AuNCs nanocomposite structure were prepared through coating of gold nanoparticles (AuNPs) with gelatin/AuNCs. Characterization and morphology of synthesized nanocomposite showed successful formation of AuNPs@gelatin/AuNCs. Constructed nanocomposite exhibited internal FRET occurrence and fluorescence quenching of AuNCs due to proximity of AuNCs/AuNPs structures. Hydrolysis effect of MMPs enzyme on AuNPs@gelatin/AuNCs in saline buffer induced changes in surface plasmon resonance (SPR) of gold nanoparticles and also enhanced the emitted fluorescence by AuNCs due to inhibition of internal FRET process. The proposed platform served as the efficient approach for semi-quantitative detection of MMP-9 enzyme by naked eye and precise activity detection with LOD of 2 ng/mL calorimetrically and 0.25 ng/mL fluorometrically. The approach was also showed convenient recovery for detection of MMP-9 enzyme in human serum matrix. Our work provides an efficient, convenient and practical tool for simple identification and precise detection of MMP-9 enzyme.