Application of 3D magnetic nanocomposites: MXene-supported Fe3O4@CS nanospheres for highly efficient adsorption and separation of dyes

MXene-encapsulated ZIF-8@Liposomes for NIR-enhanced photothermal therapy in hepatocellular carcinoma treatment: In vitro, in vivo, and in silico study

Photothermal therapy (PTT) utilizes near-infrared (NIR) light to enhance localized, non-invasive cancer treatments and drug delivery systems (DDS). Combination chemotherapy with PTT (chemo-PTT) offers multiple therapeutic advantages, involving synergistic effects, reduced side effects, and decreased drug toxicity. In this study, 2D titanium carbide (Ti3C2Tx) MXene nanosheets were encapsulated in a zeolitic imidazolate framework-8 (ZIF-8) to form (MX-ZIF-8) nanoparticles (NPs) for PTT applications. Sorafenib (SB), an anticancer drug was loaded onto MX-ZIF-8 and further modified with a liposomes (LPs) lipid bilayer to create (SB-MX-ZIF-8@LPs) nanocomposites. TEM imaging revealed that SB-MX-ZIF-8@LPs had a lamellar structure and spherical shape, with an average diameter of 75.2 nm and a zeta potential (ZP) of -8.4 ± 4.5 mV. Additionally, the PT stability, drug encapsulation, and in-vitro release kinetics of SB-MX-ZIF-8@LPs were assessed. These nanocomposites exhibited an impressive PT conversion efficiency of 55 % at 50 μg/mL under NIR irradiation. The cumulative release of SB from SB-MX-ZIF-8@LPs reached 86.15 % at pH 7.4 and 89.3 % at pH 4.8 under NIR over a period of 72 h, with an encapsulation efficiency of 87.34 %. MTT assays revealed strong cytotoxicity against HepG2 cells, with SB-MX-ZIF-8@LPs showing an IC50 value of 2.7 μg/mL and inducing approximately 96 % total apoptosis. The SB-MX-ZIF-8@lip nanocomposite demonstrated excellent biological stability in a serum environment, retaining over 98 % of sorafenib and maintaining consistent particle size (∼347 nm) over 30 days. An in vivo xenograft study in BALB/c mice further demonstrated the efficacy of SB-MX-ZIF-8@LPs, with this treatment group showing the smallest tumor volume compared to other groups and a significantly higher tumor volume reduction than SB alone. Molecular docking studies indicated that SB exhibited strong binding affinities particularly with ABL1 (-8.7 kcal/mol) and EGFR (-9.3 kcal/mol). Docking interactions between MXene and SB, conducted using the Hdock Server, resulted in a docking score of -10.53, with one bond forming at a distance of 4 Å. These findings were consistent with experimental results, highlighting the favorable interaction between MXene and SB. ADMET analysis confirmed that MX-ZIF-8@LPs possessed favorable drug carrier properties, including high intestinal absorption (96.6 %), and low toxicity supporting its potential as an effective DDS for cancer therapy.

Flexible self-standing amidoxime-functionalized MXene membrane for electrochemical uranium extraction

The presence of radioactive U(VI) ions in sewage poses a significant threat to both the ecological environment and human health. In recent years, an electricity-driven remediation strategy has emerged as aprominent technique for the elimination of radionuclides. Specifically, the square wave transformation method is an emerging technology for electrochemical separation and enrichment of uranium. It offers several merits, such as high extraction capacity, facile recovery of products, and effective suppression of water decomposition. However, conventional electrodes typically require the utilization of adhesives, which severely restricts their adsorption performance. In this study, we fabricated a self-supporting membrane electrode based on amidoxime-functionalized Ti3C2Tx MXene (TCP) for efficient extraction of uranium from radioactive solutions. The polyamidoxime (PAO) is incorporated into the interlayer of Ti3C2Tx through non-covalent bonds, leading to an increase in interlayer spacing and specific surface area while also providing an abundance of specific binding sites. Notably, by applying an alternating current (AC) voltage ranging from -5 to 0 V, uranyl ions can migrate and concentrate onto TCP membrane, achieving an exceptional extraction capacity of 2809 mg/g. Further characterization confirmed that the captured uranium(VI) was reduced to U(V), and then the unstable U(V) was re-oxidized to U(VI), eventually generating Na2O7U22 precipitates in the presence of Na+. Considering its remarkable electro-extraction performance and convenient preparation process, the TCP membrane electrode is regarded as a promising candidate for U(VI) extraction from wastewater.

Bionic Capsule Lithium-Ion Battery Anodes for Efficiently Inhibiting Volume Expansion

Magnetite (Fe3O4) has a large theoretical reversible capacity and rich Earth abundance, making it a promising anode material for LIBs. However, it suffers from drastic volume changes during the lithiation process, which lead to poor cycle stability and low-rate performance. Hence, there is an urgent need for a solution to address the issue of volume expansion. Taking inspiration from how glycophyte cells mitigate excessive water uptake/loss through their cell wall to preserve the structural integrity of cells, we designed Fe3O4@PMMA multi-core capsules by microemulsion polymerization as a kind of anode materials, also proposed a new evaluation method for real-time repair effect of the battery capacity. The Fe3O4@PMMA anode shows a high reversible specific capacity (858.0 mAh g-1 at 0.1 C after 300 cycles) and an excellent cycle stability (450.99 mAh g-1 at 0.5 C after 450 cycles). Furthermore, the LiNi0.8Co0.1Mn0.1O2/Fe3O4@PMMA pouch cells exhibit a stable capacity (200.6 mAh) and high-capacity retention rate (95.5 %) after 450 cycles at 0.5 C. Compared to the original battery, the capacity repair rate of this battery is as high as 93.4 %. This kind of bionic capsules provide an innovative solution for improving the electrochemical performance of Fe3O4 anodes to promote their industrial applications.

Novel three-dimensional fibrous covalent organic frameworks constructed via silver amalgam bridging for efficient organic dye adsorption and removal

The construction of covalent organic frameworks (COFs) with unique structures has great significance in exploring the structure-function relationship and extending their potential applications. Fibrous COFs have demonstrated superior performance in specific application scenarios owing to the distinctive three-dimensional (3D) structure. Herein, we report a facile strategy for the fabrication of 3D COF nanofiber by exploiting silver amalgam as a bridging agent to assemble one-dimensional-extended PA-COF modules into a tubular structure. Dimensions of the obtained 3D COF nanofiber were predicted by DFT calculations, and the nanofiber was endowed with the merits of favorable uniformity and high stability. Due to the enhanced exposure of conjugatable binding sites for dye retention offered by the novel 3D architecture, the PA-COF nanofiber exhibits fast adsorption (within 5 min) and superior adsorption capacity to various organic dyes, e.g., 1717 mg g-1 for methylene blue (MB) and 978.3 mg g-1 for methyl orange (MO). Moreover, the PA-COF nanofiber shows excellent reusability in dye adsorption, which makes it a potential medium for removing dye pollutants from wastewater. This work presents an effective strategy to construct COF materials with unique architecture and potential prospects in the fields of separation and wastewater treatment.

Lignin-assisted electronic modulation on NiSe/FeOx heterointerface for boosting electrocatalytic oxygen evolution reaction

The development of productive and durable non-precious metal catalysts for the sluggish oxygen evolution reaction (OER) is critical for water splitting. Herein, a novel NiSe-FeOx heterojunction encapsulated in lignin-derived carbon layer (NiSe-FeOx@LC) was synthesized via hydrothermal self-assembly and in-situ pyrolysis. NiSe-FeOx@LC exhibited excellent OER performance with an overpotential of 265 mV at 50 mA·cm-2, a Tafel slope of 83 mV·dec-1, as well as long-term stability. Both experimental and DFT calculation results indicated that the doping of FeOx into NiSe@LC successfully optimized the dual interface structure between NiSe and FeOx, thereby promoted the d-bands orbital hybridization, that facilitated electron transfer. Besides, the carbon coating effectively protected the NiSe-FeOx components from leaching and agglomerating during the reaction. This study provides insight into the significance of lignin-derived carbon-encapsulated metallic catalyst for electrocatalytic OER process.

Biodiesel Production from Waste Cooking Oil Using Recombinant Escherichia coli Cells Immobilized into Fe3O4-Chitosan Magnetic Microspheres

Developing reusable and easy-to-operate biocatalysts is of significant interest in biodiesel production. Here, magnetic whole-cell catalysts constructed through immobilizing recombinant Escherichia coli cells (containing MAS1 lipase) into Fe3O4-chitosan magnetic microspheres (termed MWCC@MAS1) were used for fatty acid methyl ester (FAME) production from waste cooking oil (WCO). During the preparation process of immobilized cells, the effects of chitosan concentration and cell concentration on their activity and activity recovery were investigated. Optimal immobilization was achieved with 3% (w/v) chitosan solution and 10 mg wet cell/mL cell suspension. Magnetic immobilization endowed the whole-cell catalysts with superparamagnetism and improved their methanol tolerance, enhancing the recyclability of the biocatalysts. Additionally, we studied the effects of catalyst loading, water content, methanol content, and reaction temperature on FAME yield, optimizing these parameters using response surface methodology and Box-Behnken design. An experimental FAME yield of 89.19% was gained under the optimized conditions (3.9 wt% catalyst loading, 22.3% (v/w) water content, 23.0% (v/w) methanol content, and 32 °C) for 48 h. MWCC@MAS1 demonstrated superior recyclability compared to its whole-cell form, maintaining about 86% of its initial productivity after 10 cycles, whereas the whole-cell form lost nearly half after just five cycles. These results suggest that MWCC@MAS1 has great potential for the industrial production of biodiesel.

Remarkable purification of organic dyes by NiOOH-modified industrial waste residues

Extracting functional materials from industrial waste residues to absorb organic dyes can maximize waste reuse and minimize water pollution. However, the extraordinarily low purification efficiency still limits the practical application of this strategy. Herein, the lamellar NiOOH is in-situ anchored on the industrial waste red mud surface (ARM/NiOOH) as an adsorbent to purify organic dyes in wastewater. ARM/NiOOH adsorbent with high specific surface area and porosity provides considerable active sites for the congo red (CR), thereby significantly enhancing the removal efficiency of CR. Besides, we fit a reasonable adsorption model for ARM/NiOOH adsorbent and investigate its adsorption kinetics. Resultantly, ARM/NiOOH adsorbent can remarkably adsorb 348.0 mg g-1 CR within 5 min, which is 7.91 times that of raw RM. Our work provides a strategy for reusing industrial waste and purifying sewage pollution, which advances wastewater treatment engineering.

Promising adsorbent for dye detoxification: Exploring the potential of chitosan sodium carboxymethylcellulose silk fibroin aerogel

The main goal of this study is to create a CS-CMC-SF aerogel consisting of chitosan sodium carboxymethylcellulose and silk fibroin. The aerogel is designed to remove types of dyes from water while also being environmentally friendly. This innovative adsorbent has been optimized for extracting both cationic and anionic dyes from solutions. It incorporates chitosan sodium carboxymethylcellulose and silk filament fibers to enhance its strength. Experimental data illustrates that the CS-CMC-SF aerogel possesses remarkable adsorption capabilities - 5461.77 mg/g for Congo Red (CR), 2392.83 mg/g for Malachite Green (MG), and 1262.20 mg/g for Crystal Violet (CV). A kinetic study aligns with the pseudo-second-order kinetic model suggesting predominant chemisorption phenomena occur during adsorption process. Isotherm analysis further identifies multilayered adsorption occurring on irregularly shaped surfaces of the aerogel while thermodynamic assessments validate exothermic and spontaneous characteristics inherent in its absorption mechanism. Several analytical methods such as SEM, FT-IR, XRD, and XPS were employed to examine physicochemical attributes tied to this unique material design conceptually; identifying mechanisms including pore filling, π-π interactions, ion exchange activity, electrostatic connections along with hydrogen bonding inducing overall superior performance output. Furthermore substantial soil biodegradability alongside compostable features associated with our proposed CS-CMC-SF aerogels established it's potential suitability within applications demanding sustainable options thereby validating its underlying ecological credibility.

Constructing N,S co-doped network biochar confined CoFe2O4 magnetic nanoparticles adsorbent: Insights into the synergistic and competitive adsorption of Pb2+ and ciprofloxacin

To solve the problem of biochar lack of adsorption sites for heavy metal ions and the difficulty of recycling, CoFe2O4 magnetic nanoparticles confined in nitrogen, sulfur co-doped 3D network biochar matrix (C-CoFe2O4/N,S-BC) was designed and fabricated successfully. The obtained C-CoFe2O4/N,S-BC displays remarkable adsorption performance for both Pb2+ and ciprofloxacin (CIP) removal at the single or binary system due to the role of N,S as metal ion anchoring compared to the N,S-free sample (CoFe2O4/BC). N,S co-doped BC not only participates in adsorption reaction but also effectively inhibites the agglomeration of CoFe2O4 nanoparticles and increases the active sites as a carrier at the same time. In the single system, CoFe2O4/N,S-BC demonstrates a fast adsorption rate (equilibrium time: 30 min) and high adsorption capacity (224.77 mg g-1 for Pb2+, 400.11 mg g-1 for CIP) towards Pb2+ and CIP. The adsorption process is befitted pseudo-second-order model, and the equilibrium data are in great pertinence with Langmuir model. In the binary system, the maximum adsorption capacity of CoFe2O4/N,S-BC for Pb2+ and CIP is 244.80 mg g-1 (CIP: 10.00 mg L-1) and 418.42 mg g-1 (Pb2+: 10.00 mg L-1), respectively. The adsorption mechanism is discussed based on the experimental results. Moreover, C-CoFe2O4/N,S-BC shows good practical water treatment capacity, anti-interference ability and stable reusability (the removal efficiency＞80% after eight cycles). The rapid, multifunctional, reusable, and easily separable adsorption properties make C-CoFe2O4/N,S-BC promising for efficient environmental remediation. This study also offers a viable method for the construction of adsorption material for complex wastewater treatment.

A biosensor based on Fe3O4@MXene-Au nanocomposites with high peroxidase-like activity for colorimetric and smartphone-based detection of glucose

A novel magnetic nanozyme Fe₃O₄@MXene-Au nanocomposite, which possessed higher peroxidase-like activity than that of Fe₃O₄ nanoparticles and Fe₃O₄@MXene nanocomposites, was developed. The outstanding magnetic properties of the nanozyme endowed it with the ability of simple and rapid separation, achieving great recyclability. Based on Fe₃O₄@MXene-Au nanocomposites and glucose oxidase (Glu Ox), a highly selective colorimetric biosensor for glucose detection was developed. Fe₃O₄@MXene-Au nanocomposites can catalyze H₂O₂ produced from glucose catalyzed by glucose oxidase to ·OH and oxidize colorless 3,3',5,5'-tetramethylbenzidine (TMB) to blue oxidized TMB (oxTMB) with a significant absorbance at 652 nm. The linear range of glucose was 0-1.4 mM under optimal conditions, with a limit of detection (LOD) of 0.11 mM. Glucose in human whole blood was successfully detected with satisfactory recoveries. Furthermore, a facile agarose hydrogel detection platform was designed. With smartphone software, glucose detection can be realized by the agarose hydrogel platform, demonstrating the potential in on-site and visual detection of glucose.

Research on the Antibacterial Properties of MXene-Based 2D-2D Composite Materials Membrane

Novel MXene-based two-dimensional (2D) membranes are widely used for water purification due to their highly controllable structure and antibacterial properties. However, in the process of membrane separation, the problems of membrane fouling, especially biological fouling, limits the further application of MXene-based membranes. In this study, in order to improve the antibacterial and separation properties of membranes, three kinds of MXene-based 2D-2D composite membranes (M2~M4) were prepared using polyethersulfone (PES) as the substrate, which were GO@MXene, O-g-C₃N₄@MXene and BiOCl@MXene composite membranes respectively. The results showed that the antibacterial activity of M2~M4 against Escherichia coli and Staphylococcus aureus was further improved, especially the antibacterial ratio of M4 against Escherichia coli and Staphylococcus aureus was up to 50% and 82.4%, respectively. By comparing the surface morphology of MXene membrane and modified membrane treated bacteria through scanning electron microscopy (SEM), it was found that the cell density on modified membrane was significantly lower than that of pure MXene membrane.

Preparation of paramagnetic ferroferric oxide-calcined layered double hydroxide core-shell adsorbent for selective removal of anionic pollutants

Adsorption is one of the most common methods of pollution treatment. The selectivity for pollutants and recyclability of adsorbents are crucial to reduce the treatment cost. Layered double hydroxide (LDH) materials are one type of adsorbent with poor recyclability. Prussian blue (PB) is a sturdy and inexpensive metal-organic framework material that can be used as the precursor for synthesizing paramagnetic ferroferric oxide (Fe₃O₄). It is intriguing to build some reusable adsorbents with magnetic separation by integrating LDH and PB. In this work, paramagnetic Fe₃O₄-calcined LDH (Fe₃O₄@cLDH) core-shell adsorbent was designed and prepared by the calcination of PB-ZnAl layered double hydroxide (PB@LDH) core-shell precursor, which exhibits high anionic dyes selectivity in wastewater solutions. The paramagnetism and adsorption capability of Fe₃O₄@cLDH come from the Fe₃O₄ core and calcined ZnAl-LDH shell, respectively. Fe₃O₄@cLDH shows an adsorption capacity of 230 mg g^-1 for acid orange and a high selectivity for anionic dyes in cation-anion mixed dye solutions. The regeneration process indicates that the high selectivity for anions is related to the specific hydration recovery process of ZnAl-LDH. The synergistic effect of the paramagnetic Fe₃O₄ core and calcined ZnAl-LDH shell makes Fe₃O₄@cLDH an excellent magnetic separation adsorbent with high selectivity to anions.

Effective removal of brilliant green with magnetic barium phosphate composites: factor analysis and mechanism study

In this work, magnetic barium phosphate (FBP) composites with different content of commercial Fe₃O₄ nanoparticles were easily prepared by a one-step hydrothermal method. FBP composites with a magnetic content of 3% (FBP3) were studied as the example for the removal of an organic pollutant (Brilliant Green, BG) from the synthetic medium. The adsorption study was executed under the variation of different experimental conditions, such as solution pH (5 ~ 11), dosage (0.02 ~ 0.20 g), temperature (293 ~ 323 K), and the contact time (0 ~ 60 min) on the removal of BG. For comparison purposes, the one-factor-at-a-time (OFAT) approach and Doehlert matrix (DM) were both employed to investigate the factor impacts involved. FBP3 showed a high adsorption capacity of 1419.3 ± 10.0 mg/g for at 25 °C and pH = 6.31. The kinetics study revealed the pseudo-second-order kinetic model as the best-fitted model, and the thermodynamic data fit well with the Langmuir model. The possible adsorption mechanisms involved are the electrostatic interaction and/or hydrogen bonding of PO₄^3-…N⁺/C-H and HSO₄^-…Ba²⁺ between FBP3 and BG. Furthermore, FBP3 showed good easy reusability and high capacities for BG removal. Our results provide new insights for developing low-cost, efficient, and reusable adsorbent to remove BG from industrial wastewater.

Superhydrophobic aerogel blanket with magnetic and solar heating effect enables efficient continuous cleanup of highly viscous crude oil

Rapid cleanup of highly-viscous oil spills the sea is eagerly desired while still remains a great challenge. Hydrophobic and lipophilic adsorbents are regarded as ideal candidate for oil spill remediation. However, traditional adsorbents are not suitable for viscous crude oil, which would block the porous structure and lead to poor adsorption efficiency. In this work, a non-contact responsive superhydrophobic SiO₂ aerogel blankets (SAB) with excellent magnetic and solar heating effect for efficient removal of viscosity oils under harsh environments was developed, via assembled MXene and Fe₃O₄/polydimethylsiloxane layer-by-layer along the SAB skeleton (Fe₃O₄/MXene@SAB). The Fe₃O₄/MXene@SAB exhibited excellent compression tolerance (compression stress 70.69 kPa), superhydrophobic performance (water contact angle 166°), and corrosion resistance (weak acid/strong base). Due to high water repellency and stable porous structure, the Fe₃O₄/MXene@SAB could successfully separate oil-water mixture, while with remarkable separation flux (1.50-3.19 × 10⁴ L m^-2 h^-1), and separation efficiency (99.91-99.98 %). Furthermore, the responsive Fe₃O₄/MXene@SAB also showed outstanding magnetic-heating and solar-heating conversion efficiency, which could continuously separate high viscosity crude oil from seawater by pump even under relatively low magnetic fields and mild sun. The superhydrophobic blankets hold great promise for efficient treatment of heavy oil spills.

Magnetoresistive Properties of Nanocomposites Based on Ferrite Nanoparticles and Polythiophene

In the presented study, we have synthesized six nanocomposites based on various magnetic nanoparticles and a conducting polymer, poly(3-hexylthiophene-2,5-diyl) (P3HT). Nanoparticles were either coated with squalene and dodecanoic acid or with P3HT. The cores of the nanoparticles were made of one of three different ferrites: nickel ferrite, cobalt ferrite, or magnetite. All synthesized nanoparticles had average diameters below 10 nm, with magnetic saturation at 300 K varying between 20 to 80 emu/g, depending on the used material. Different magnetic fillers allowed for exploring their impact on the conducting properties of the materials, and most importantly, allowed for studying the influence of the shell on the final electromagnetic properties of the nanocomposite. The conduction mechanism was well defined with the help of the variable range hopping model, and a possible mechanism of electrical conduction was proposed. Finally, the observed negative magnetoresistance of up to 5.5% at 180 K, and up to 1.6% at room temperature, was measured and discussed. Thoroughly described results show the role of the interface in the complex materials, as well as clarify room for improvement of the well-known magnetoelectric materials.

High-efficiency adsorption removal of CR and MG dyes using AlOOH fibers embedded with porous CoFe2O4 nanoparticles

Owing to the toxicity and difficulty in degradation, how to the effective separation for the residual dyes in the aqueous solution is still an issue with great challenge in the area of environmental protection. Now, to high-efficiency removal of organic dyes from the aqueous solution, we design a unique AlOOH/CoFe₂O₄ adsorbent with porous CoFe₂O₄ nanoparticles embedded on the AlOOH fibers using a simple hydrothermal technique and calcination process. The structural properties and surface characteristics of the AlOOH/CoFe₂O₄ composites are detailedly analyzed by XRD, FTIR, XPS, TEM and SEM. Here, the high S_BET and specific porous structure are beneficial to improve the adsorption performance of AlOOH/CoFe₂O₄ adsorbents. Especially, when the molar ratio of AlOOH to CoFe₂O₄ in the AlOOH/CoFe₂O₄ fibers is 1:1, an optimal performance on adsorbing anionic Congo red (CR) and cationic methyl green (MG) dyes can be obtained at pH = 6.29, where the corresponding maximum adsorption capacities reach up to 565.0 and 423.7 mg g^-1, respectively. Factors leading to the change in the ability of adsorbing CR and MG dyes are systematically discussed, including contact time, temperature, initial concentrations, and pH values of the solutions. Meanwhile, the uptake of CR and MG dyes can best conform to Langmuir isotherm model and pseudo-second-order adsorption kinetics. The thermodynamic analysis verifies that the dye adsorption process is spontaneous and endothermic. Moreover, from the point view of practical application, the good reusability further makes the as-synthesized magnetic AlOOH/CoFe₂O₄ composite be a perfect adsorbent with efficiently removing both anionic and cationic dyes from aqueous solutions.

MXenes and MXene-supported nanocomposites: a novel materials for aqueous environmental remediation

Water contamination has become a significant issue on a global scale. Adsorption is a cost-effective way to treat water and wastewater compared to other techniques such as the Advanced Oxidation Processes (AOPs), photocatalytic degradation, membrane filtration etc. Numerous research experts are continuously developing inexpensive substances for the adsorptive removal of organic contaminants from wastewater. A fresh and intriguing area of inquiry has emerged as a result of the development of MXenes. This article aims to provide a preliminary understanding of MXenes from synthesis, structure, and characterization to the scope of further research. The applications of MXenes as a new generation adsorbent for remediation of various kinds of organic pollutants and heavy metals from wastewater are also summarized. MXenes with altered surfaces may make effective adsorbents for wastewater treatment. Lastly, the mechanism of adsorption of organic contaminants and heavy metals on MXenes is also discussed for a better understanding of the readers.

MXene/Ferrite Magnetic Nanocomposites for Electrochemical Supercapacitor Applications

MXene has been identified as a new emerging material for various applications including energy storage, electronics, and bio-related due to its wider physicochemical characteristics. Further the formation of hybrid composites of MXene with other materials makes them interesting to utilize in multifunctional applications. The selection of magnetic nanomaterials for the formation of nanocomposite with MXene would be interesting for the utilization of magnetic characteristics along with MXene. However, the selection of the magnetic nanomaterials is important, as the magnetic characteristics of the ferrites vary with the stoichiometric composition of metal ions, particle shape and size. The selection of the electrolyte is also important for electrochemical energy storage applications, as the electrolyte could influence the electrochemical performance. Further, the external magnetic field also could influence the electrochemical performance. This review briefly discusses the synthesis method of MXene, and ferrite magnetic nanoparticles and their composite formation. We also discussed the recent progress made on the MXene/ferrite nanocomposite for potential applications in electrochemical supercapacitor applications. The possibility of magnetic field-assisted supercapacitor applications with electrolyte and electrode materials are discussed.

MXene-Based Photocatalysts in Degradation of Organic and Pharmaceutical Pollutants

These days, explorations have focused on designing two-dimensional (2D) nanomaterials with useful (photo)catalytic and environmental applications. Among them, MXene-based composites have garnered great attention owing to their unique optical, mechanical, thermal, chemical, and electronic properties. Various MXene-based photocatalysts have been inventively constructed for a variety of photocatalytic applications ranging from pollutant degradation to hydrogen evolution. They can be applied as co-catalysts in combination with assorted common photocatalysts such as metal sulfide, metal oxides, metal-organic frameworks, graphene, and graphitic carbon nitride to enhance the function of photocatalytic removal of organic/pharmaceutical pollutants, nitrogen fixation, photocatalytic hydrogen evolution, and carbon dioxide conversion, among others. High electrical conductivity, robust photothermal effects, large surface area, hydrophilicity, and abundant surface functional groups of MXenes render them as attractive candidates for photocatalytic removal of pollutants as well as improvement of photocatalytic performance of semiconductor catalysts. Herein, the most recent developments in photocatalytic degradation of organic and pharmaceutical pollutants using MXene-based composites are deliberated, with a focus on important challenges and future perspectives; techniques for fabrication of these photocatalysts are also covered.

Cu-Y2O3 Catalyst Derived from Cu2Y2O5 Perovskite for Water Gas Shift Reaction: The Effect of Reduction Temperature

Cu2Y2O5 perovskite was reduced at different temperatures under H2 atmosphere to prepare two Cu-Y2O3 catalysts. The results of the activity test indicated that the Cu-Y2O3 catalyst after H2-reduction at 500 °C (RCYO-500) exhibited the best performance in the temperature range from 100 to 180 °C for water gas shift (WGS) reaction, with a CO conversion of 57.30% and H2 production of 30.67 μmol·gcat−1·min−1 at 160 °C and a gas hourly space velocity (GHSV) of 6000 mL·gcat−1·h−1. The catalyst reduced at 320 °C (RCYO-320) performed best at the temperature range from 180 to 250 °C, which achieved 86.44% CO conversion and 54.73 μmol·gcat−1·min−1 H2 production at 250 °C. Both of the Cu-Y2O3 catalysts had similar structures including Cu°, Cu+, oxygen vacancies (Vo) on the Cu°-Cu+ interface and Y2O3 support. RCYO-500, with a mainly exposed Cu° (100) facet, was active in the low-temperature WGS reaction, while the WGS activity of RCYO-320, which mainly exposed the Cu° (111) facet, was greatly enhanced above 180 °C. Different Cu° facets have different abilities to absorb H2O and then dissociate it to form hydroxyl groups, which is the main step affecting the catalytic rate of the WGS reaction.