Hydrothermal Route Research Articles

Rational design and synthesis of BiOF micro/nanostructures with enhanced photocatalytic properties

BiOF with tunable morphologies (polygonal disk-shaped columns, polygonal flakes and square flakes) have been prepared via a facile hydrothermal route, in which nitrilotriacetic acid (NTA) was used as a structure directing reagent. It was found that the morphologies and crystalline structures of the as-obtained BiOF were dependent on the NTA dosage and the pH value. Based on the observation of the photocatalytic selectivity of typical polygonal disk-shaped columns of BiOF towards different types of organic dyes, we further investigated the photocatalytic activities of the BiOF with different morphologies by the degradation of malachite green (MG) solution under UV light irradiation. The results showed that disk-shaped columns of BiOF had the best photocatalytic activity, and the degradation rate of MG reached 95.34 % after 20 min of irradiation. The photocatalytic efficiency was much higher than those of other morphological BiOF micro/nanostructures. The results of this study strongly indicate that BiOF has a broad application prospect in the field of photocatalysis.

Engineering a staggered type-II Bi2WO6/WO3 heterojunction with improved photocatalytic activity in wastewater treatment

In recent years, the removal organic pollutants from wastewater by advanced oxidation processes, especially photocatalysis, has become a meaningful approach due to its eco-friendliness and low cost. Herein, staggered type-II Bi2WO6/WO3 heterojunction photocatalysts were prepared by a facile hydrothermal route and investigated by modern physicochemical methods (X-ray diffraction, scanning electron microscopy, low-temperature nitrogen adsorption-desorption, and diffuse reflectance spectroscopy). The optimized BWOW-5 photocatalyst exhibited a H2O2-assisted photocatalytic methylene blue removal efficiency of 94.1% (k = 0.01414 min−1) within 180 min under optimal reaction conditions, which is much higher than that of unmodified Bi2WO6 and WO3 due to efficient separation of the photogenerated charge carriers. The trapping experiments demonstrated that photogenerated hydroxyl radicals and holes play a key role in the photodegradation reaction. Moreover, the optimized BWOW-5 heterojunction photocatalyst exhibited excellent activity in the H2O2-assisted degradation of other pollutants, namely phenol, isoniazid, levofloxacin, and dibenzothiophene with the removal rate of 63.1, 73.6, 95.0, and 72.4%, respectively. This investigation offers a design strategy for Bi2WO6-based multifunctional photocatalytic composites with improved activity for organic pollutant degradation.

Si,N co-doped carbon quantum dots in mesoporous molecular sieves: A fluorescence sensing platform for Cr(VI) detection

Carbon quantum dots (CQDs) are highly efficient fluorescent probes for metal ion detection; however, they are limited by non-uniform particle size, aggregation, and the inability to facilitate quantitative analysis. Herein, a smart host–guest strategy is utilized, wherein CQDs are immobilized in mesoporous molecular sieves, proving to be an effective method to minimize these drawbacks. Si,N-CQDs@SBA-15 is successfully synthesized by the one-step hydrothermal route using Si,N-CQDs precursor materials as guests and the mesoporous molecular sieve SBA-15 as the host. A good linear relationship between the concentration of Cr(VI) ions and fluorescent intensity is observed from 0 μM to 100 μM (R2 = 0.9986). Thelimitofdetection(LOD) is 0.213 μM, approximately three times lower than that of pristine Si,N-CQDs (0.677 μM). Additionally, Si,N-CQDs@SBA-15 exhibit good detection selectivity for Cr(VI) detection over other metal ions. Moreover, a smartphone-based laboratory device and RGB analysis app are employed to capture and analyze fluorescence images, revealing a LOD for Cr(VI) of 0.201 μM. Förster Resonance Energy Transfer (FRET) is identified as the possible mechanism for the fluorescence quenching of Si,N-CQDs@SBA-15 by Cr(VI) through UV–vis and fluorescence experiments. The practicability of the synthesized fluorescent probes is further validated in river water, yielding satisfactory spiked recoveries ranging from 99.24 % to 106.21 %.

Mg–Fe Layered Double Hydroxides/Polyacrylonitrile Nanofibers for Solar-Light Induced Peroxymonosulfate Elimination of Tetracycline Hydrochloride

The photo-induced peroxymonosulfate (photo-PMS) reaction is a promising route to eliminate antibiotics from waste water. To achieve excellent photo-PMS activity in Mg–Fe layered double hydroxides (LDHs) for tetracycline hydrochloride (TCH) degradation under simulative solar-light irradiation, Mg–Fe LDHs-loaded polyacrylonitrile (Mg–Fe/PAN) nanofibers were in-situ prepared via the hydrothermal route. For comparison to the photocatalysis and photo-PMS process, the Mg–Fe/PAN-assisted photo-PMS process exhibited a better elimination activity for TCH elimination. In addition, the photo-PMS activities of Mg–Fe/PAN composites were greatly affected by Mg–Fe LDHs content, TCH concentration, pH, and inorganic salts. Among these Mg–Fe/PAN composites, the optimal MgFe2/PAN with a Mg/Fe molar ratio of 1:2 and a nominal Mg–Fe LDHs content of 2.0 wt. % removed 81.31% TCH solution of 80 mg L−1 TCH within 120 min. This enhanced photo-PMS capacity of MgFe2/PAN was ascribed to the abundant active sites formed by functional groups and oxygen defects for efficient TCH species adsorption and photon capturing, and the tight interface between Mg–Fe LDHs nanoparticles and PAN nanofibers for the rapid separation and transfer of photoinduced e−/h+ pairs. SO4•− and •O2− radicals were vital for the MgFe2/PAN-assisted photo-PMS reaction.

MXene/cobalt ferrite/carbon materials based composites for efficient microwave absorption

In the present study, cobalt ferrite (CF) nanoparticles were in-situ grown on MXene/carbon-based materials (activated carbon (AC), MWCNT, and GO) to develop composites via facile hydrothermal route. The MXene/CF/MWCNTs composite (FMCNT4) achieved an excellent maximum reflection loss (RLmax) of −67.04 dB at 16.24 GHz & a thickness of 5.94 mm, whereas at the thickness of 5.86 mm, the FMCNT4 obtained a maximum effective absorption bandwidth (EAB, RL < −10 dB) of 2.73 GHz. On the other hand, replacing MWCNTs with AC in the composite (FMAC4) showed RLmax of −46.52 dB at 18 GHz and 5.1 mm thickness, it also got an EAB of 2.54 GHz at 5.5 mm thickness. The MXene/CF/GO composite (FMGO5) obtained RLmax = −17.31 @ 17.12 GHz & 6 mm. The composite having MWCNTs showed the best performance, and the reason for this remarkable MW absorption performance originated from the high impedance matching followed by dielectric polarization and magnetic losses in the composite. The formation of multiple heterointerfaces between MXene, CF, and MWCNTs enhanced the interfacial polarization, whereas the conducting MXene and MWCNTs also contributed to conduction polarization. Thus, the present investigation showcases FMCNT as an excellent synergetic nanocomposite for MW absorption applications.

Direct Z-scheme charge transfer Bi2O3/UiO-66-NH2 heterojunctions for boosted photocatalytic degradation of tetracycline hydrochloride in different water systems

The development of hybrid heterostructure photocatalysts with enhanced visible light absorption capacity holds significant importance in environmental remediation. However, the challenge persists in exploiting strong visible-light responsive photocatalysts with both high efficiency and stability. Herein, we successfully synthesized a hybrid Z-scheme heterojunction of Bi2O3 and UiO-66-NH2 (Bi2O3/UiO-66-NH2) through a simple hydrothermal route. The visible light photocatalytic performance of Z-scheme Bi2O3/UiO-66-NH2 heterojunction is systematically evaluated for persistent antibiotic tetracycline hydrochloride (TC-HCl) both in the clean and real water matrix. All heterojunction catalysts exhibit superior photodegradation capabilities compared to pristine Bi2O3 and UiO-66-NH2. The optimal ratio of the two components heterojunction (BUN-150), in particular, demonstrates the highest removal efficiencies for TC-HCl (95 %) within a 90-min timeframe. This remarkable photocatalytic performance is credited to the Z-scheme charge transfer occurring at the interface of Bi2O3 and UiO-66-NH2 in Bi2O3/UiO-66-NH2 heterojunction. The active species experiments and electron paramagnetic resonance analyses are conducted to identify the active reactive species during the TC-HCl degradation (·OH, h+, and ·O2−), and a precise photocatalytic degradation mechanism is explained. Additionally, the photodegradation intermediates of TC-HCl are detected using the HPLC-MS analysis to explain the degradation pathways of TC-HCl. This research paves the way for the development of novel Z-scheme Bi2O3-based heterojunction catalysts for outstanding photocatalytic applications.

Comparing magnetic characteristics of CoSe3xFe2–4xO4 (x ≤ 0.10) spinel ferrite nanoparticles synthesized via Sol-Gel and hydrothermal approaches

In this study, Se substituted Co spinel ferrite nanoparticles (CoSe3xFe2–4xO4 (x ≤ 0.10), CoSe SFNPs) have been synthesized via sol-gel (SG) and hydrothermal (HT) routes and their structural, magnetic and morphological features have been compared. The effect of both the Se substitution and the method of synthesis on the structural, morphological and magnetic features of the host CoFe2O4 have been investigated. The structure and morphology of the SFNPs were examined using XRD, EDX, SEM, TEM and HR-TEM methods. XRD analysis confirmed the single-phase formation of CoSe SFNPs for both HT and SG routes. A TEM study for the HT process demonstrated the development of spherical nanoparticles with uniform size, whereas the SG procedure produced NPs with an indeterminate shape. By examining the hysteresis loops at 300 and 20 K and analysing the temperature-dependent changes in magnetization (M), the magnetic characteristics of CoSe (x ≤ 0.10) SFNPs prepared by the SG and HT methods were investigated. CoSe SFNPs possess magnetically soft and hard natures at 300 and 20 K, respectively. Under each synthesis condition, at 20 K, the SQR values are above 0.5, which signifies well-ordered magnetic domains at this temperature. Across all the materials, as the temperature decreases, zero field cooling (ZFC) branches exhibit a non-linear decline in magnetization which becomes nearly stable in the field cooling (FC) branches. The deviation of the ZFC curve with respect to FC one is more pronounced in the case of SFNPs prepared by the HT process. Our findings demonstrate that by employing the desired synthesis method, Se dopants can be applied to achieve particular magnetic characteristics of CoFe2O4 NPs.

Harnessing solar power for enhanced photocatalytic degradation of coloured pollutants using novel Mg-doped-ZnFe2O4/S@g-C3N4 heterojunction: A facile hydrothermal synthesis approach.

The ability of heterogeneous photocatalysis to effectively remove organic pollutants from wastewater has shown great promise as a tool for environmental remediation. Pure zinc ferrites (ZnFe2O4) and magnesium-doped zinc ferrites (Mg@ZnFe2O4) with variable percentages of Mg (0.5, 1, 3, 5, 7, and 9 mol%) were synthesized via hydrothermal route and their photocatalytic activity was checked against methylene blue (MB) taken as a model dye. FTIR, XPS, BET, PL, XRD, TEM, and UV-Vis spectroscopy were used for the identification and morphological characterization of the prepared nanoparticles (NPs) and nanocomposites (NCs). The 7% Mg@ZnFe2O4 NPs demonstrated excellent degradation against MB under sunlight. The 7% Mg@ZnFe2O4 NPs were integrated with diverse contents (10, 50, 30, and 70 wt.%) of S@g-C3N4 to develop NCs with better activity. When the NCs were tested to degrade MB dye, it was revealed that the 7%Mg@ZnFe2O4/S@g-C3N4 NCs were more effective at utilizing solar energy than the other NPs and NCs. The synergistic effect of the interface formed between Mg@ZnFe2O4 and S@g-C3N4 was primarily responsible for the boosted photocatalytic capability of the NCs. The fabricated NCs may function as an effective new photocatalyst to remove organic dyes from wastewater.

Effect of carbon quantum dots doping on structural, optical, and antibacterial properties of barium tungstate nanocomposite material

Local bacterial infection remains an increasingly severe threat to human health worldwide, and infection control is still a challenging task. Carbon Quantum Dots (CQSs) and barium tungstate show antibacterial properties. CQDs doped Barium Tungstate (BaWO4) are synthesized by using a hydrothermal route and their optical and antimicrobial activities against the Gram-positive bacteria staphylococcus aureus and optical properties were investigated. The UV–Vis reveals a shift in the bandgap from 3.62 eV to 2.93 eV due to doping of CQDs in BaWO4. The structure of the CQDs/BaWO4 were studied by XRD, which shows CQDs doped BaWO4 samples possess tetragona4 werelite structure with the preferred orientation of (112) identified by XRD at 26° having crystallite size ∼ 31 nm. Nanocomposite BaWO4/CQDs exhibit a spherical-like shape and are composed of Ba, O, W and C according to the design of the experiment. Zeta sizer of CQDs by DLS shows the size of CQDs is 7.65 nm. The FT-IR shows the presence of functional groups in doped material like CC, CO, and COOH bonds which indicate that the C-dots are functionalized with epoxy, carbonyl, hydroxyl, and carboxylic acid groups. Their elemental composition and surface morphology were studied by EDS which shows the percentage variation of CQDs in BaWO4, SEM results show the change in shape of the sample by adding CQDs to BaWO4. The TEM image proves the presence of doped material in the BaWO4. The PL spectra reveals the emission spectra shift towards a higher wavelength and absorption increases. The qualitative analysis shows the antimicrobial activity and enlargement of the inhibition zone and quantitative analysis confirms it.

Toward the microporous zeolite family with tunable large-medium cage and pore opening

Modulation of zeolite porosity, including the size and type of channel and cage, is essential for catalysis and separation. Although zeolites with a variety of porous systems have been synthesized by hydrothermal or post-synthetic routes, there is still a lack of rational control of zeolite porosity in the range of large to medium pore/cage. Herein, based on the rational structure building, the structure similarity between IWV topology with large-pore opening and supercage and NES topology with medium-pore opening and medium cage is discovered. Based on the guidance of structure building, two IWV-derived daughter zeolites with different framework compositions, (Si,Ge)-ECNU-31 and (Si,Ge,Al)-ECNU-31, are hydrothermally prepared with built-in structural weakness due to the presence of a large amount of framework Ge atoms, which are utilized to prepare ECNU-32 zeolite with NES topology through subsequent post-synthetic treatment under controlled condition. It is demonstrated that the parent IWV zeolite with only Ge and Si as framework atoms is benefit in post-treatment to obtain a highly crystalline NES zeolite. In contrast, the co-existence of framework Al atoms in (Si,Ge,Al)-ECNU-31 zeolite enhances its hydrothermal stability in water. However, the treatment with acid and amine solutions causes the partial collapse of zeolite structure. Our results demonstrate that rational selection of the framework composition and post-synthetic parameters are crucial for the transformation of large-pore zeolite to medium-pore zeolite.

Development of BaMnO3 nanoparticles embedded on rGO nanosheets via facile hydrothermal route to improve water oxidation

In light of environmental problems such as the depletion of hydrocarbon resources and global warming, the use of environment-friendly power production has become crucial nowadays. Hydrogen can serve as a globally friendly energy source because the byproduct of hydrogen combustion is only water. By a hydrothermal approach, we synthesized barium manganese oxide (BaMnO3) embedded on reduced graphene oxide (rGO) as a competent electrocatalyst for OER. We utilized X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive x-rays (EDX), Brunauer Emmette Teller (BET) and Raman to determine the crystal structure, morphology, elemental composition, surface area and lattice phenomena of the fabricated rGO/BaMnO3 nanocomposite. The BaMnO3 agglomerated nanoparticles were incorporated into the mesoporous hollow carbon nanosheets to form amorphous textured embedded rGO/BaMnO3. This enhanced the intrinsic reactivity of rGO/BaMnO3 nanocomposite for the oxygen evolution reaction (OER) in addition to increasing the effective surface area of the electrolyte. The electrochemical outcomes demonstrate that synthesized nanocomposite exhibited an impressive Tafel slope (36 mV dec−1), lowest overpotential (202 mV) and remarkable stability over 35 h. Therefore, the fabricated nanocomposite displayed exceptional efficiency in OER process as well as for numerous other future applications.

Synthesis of Niobium Pentoxide and Its Reduced Graphene Oxide Nanocomposite for Enhanced Supercapacitor Applications

Synthesis of Niobium Pentoxide and Its Reduced Graphene Oxide Nanocomposite for Enhanced Supercapacitor Applications

Morphological, and Optical Properties of BaTiO3 Nano Particles

Barium titanate (BaTiO3) nano particles have garnered significant attention due to their unique structural, morphological and optical properties, which hold promise for various technological applications. This study presents a comprehensive investigation in to the synthesis potential of BaTiO3 nano particle. The synthesis of BaTiO3 nano particles was achived through various methods, including sol-gel, hydrothermal, and solvothermal routes, with meticulous control over parameters such as temperature, pH, and precursor concentration to tailor the nano particle size and morphology. The structural characterization using techniques such as x-ray diffraction (XRD) revealed the formation of pure –phase BaTiO3nanoparticles with crystallite sizes in the nanometer range, exhibiting a perovskite strucure. Morphological analysis using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) elucidated the morphology, size distribution, and surface chacteristics of the nano particles. The results showcased well –defined, uniform nano particles with controllable sizes and shapes, ranging from spherical to cubic, depending onthe synthesis conditions. futher more, the optical properties ofBaTiO3 nanoparticles were investigated using UV-visible spectroscopy and photoluminescence spectroscopy. The UV- visible spectra exhibited characteristic absorption peaks corresponding to the electronic transitions within the band structure of BaTio3,while photoluminescence spectra revealed emission peaks indicative of defect states with in the nanoparticle. These optical properties were found to be tunable by varying the nano particle size, morphology, and surface characteristics, offering opportunities for optoelectronic and photonic device applications. The key findings of this study underscore the importance of understanding the interplay between synthesis parameters and resulting structural, morphological, and optical properties of BaTiO3 nanoparticles.

Microwave-assisted hydrothermal synthesis and gas sensing properties of ZnSn(OH)6, ZnSnO3, and Zn2SnO4/SnO2 hierarchical nano-/hetero-structures

Although semiconducting metal oxide sensors present reasonable sensitivity, an improved lower detection limit and/or selectivity would allow broadening real-time monitoring applications. This work reports the growth mechanism and gas sensing performance of zinc tin oxide-based structures synthesised via a microwave-assisted hydrothermal route. The synthesised materials were characterised by X-ray diffraction (XRD), Raman and Fourier-transform infrared (FTIR) spectroscopy, scanning and scanning transmission electron microscopy (SEM and STEM), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), and nitrogen adsorption/desorption experiments. Gas sensor measurements showed that ZnSnO3 presents an outstanding lower detection limit to nitrogen dioxide (NO2), in which a 10-fold increase in electrical resistance is expected in the presence of 1 ppb NO2 at an operating temperature of 150 ˚C. Moreover, the Zn2SnO4/SnO2 heterostructure exhibited superior selectivity to NO2 relative to hydrogen (H2) and carbon monoxide (CO), exhibiting a sensor response ∼1500 times higher for the oxidising gas. Hence, it is demonstrated that nanostructures’ growth engineering can realise lower detection limits and ultra-selective high-performance gas sensor devices through a greater surface area and enhanced contact potential barriers.

Exploring the effect of concentration on hydrothermally synthesized mesoporous spherical nanoflowers of bismuth tungstate for hybrid supercapacitor and water-splitting applications

This paper describes how the synergistic effect of concentration changes the electrode conductivity and enhances the electrochemical and electrocatalytic activities of bismuth tungstate nanoflowers (BWO NFs). This research mainly aims to develop mesoporous spherical BWO NFs using a hydrothermal route. The structural analysis of the BWO NFs revealed the presence of an orthorhombic phase with a regular atomic arrangement. Scanning electron microscopy revealed that the different BWO NFs samples had nonuniform spherical NFs, which play an important role in supercapacitor and electrocatalytic applications. The identification of functional groups and stretching–bending vibrations of Bi–W–O bonds are revealed by FT-IR and Raman spectroscopy respectively. Additionally, the transmission electron microscopy and X-ray photoelectron spectroscopy confirmed the morphological, structural, and electronic states of the BWO NFs. Furthermore, the supercapacitive and electrocatalytic activity of BWO–nickel foam (NF) electrodes were investigated using an aqueous 1 M KOH electrolyte. The results revealed that the BWO-2 electrode exhibited an improved specific capacity (Csp) of (647 F/g) 72 mAh/g and excellent capacitive retention of 81 % over 5000 cycles. An asymmetrical hybrid device was fabricated using a two-electrode cell with BWO–NF and reduced graphene oxide acting as the positive and negative electrodes, respectively. The device demonstrated favorable electrochemical properties: a Csp of 52 mAh/g at 5 mV/s as well as a Csp of 46 mAh/g, the highest energy density of 32 Wh/kg, and the highest power density of 2330 W/kg at 5 mA/cm2. Furthermore, the BWO NFs were investigated for water-splitting activity, and the BWO-2 electrode was found to exhibit better electrocatalytic performance (overpotential: 328 mV, Tafel slope: 80.9 mV/dec, and electrochemical surface area: 41.2 cm2) and stability than the other electrodes. The designed asymmetric structure offers a suitable cathode material for energy storage and electrocatalytic applications.

Uniform P-Doped MnMoO4 Nanosheets for Enhanced Asymmetric Supercapacitors Performance.

Manganese molybdate has garnered considerable interest in supercapacitor research owing to its outstanding electrochemical properties and nanostructural stability but still suffers from the common problems of transition metal oxides not being able to reach the theoretical specific capacitance and lower electrical conductivity. Doping phosphorus elements is an effective approach to further enhance the electrochemical characteristics of transition metal oxides. In this study, MnMoO4·H2O nanosheets were synthesized on nickel foam via a hydrothermal route, and the MnMoO4·H2O nanosheet structure was successfully doped with a phosphorus element using a gas-solid reaction method. Phosphorus element doping forms phosphorus-metal bonds and oxygen vacancies, thereby increasing the charge storage and conductivity of the electrode material. The specific capacitance value is as high as 2.112 F cm-2 (1760 F g-1) at 1 mA cm-2, which is 3.2 times higher than that of the MnMoO4·H2O electrode (0.657 F cm-2). The P-MnMoO4//AC ASC device provides a high energy density of 41.9 Wh kg-1 at 666.8 W kg-1, with an 84.5% capacity retention after 10,000 charge/discharge cycles. The outstanding performance suggests that P-MnMoO4 holds promise as an electrode material for supercapacitors.

Developing TiCo2O4 spinel based on rGO nanosheet to enhance electrochemical performance of OER activity

The reduction of fossil fuel reserves and the deterioration of environmental conditions have led to a worldwide concern with producing significant amounts of energy in a sustainable manner. The production of electrocatalysts for the oxygen evolution reaction (OER) is imperative for widespread commercialization of water electrolyzers. The electrocatalysts must exhibit improved electrocatalytic behavior while being cost-effective. This work presents simple hydrothermal route for producing a TiCo2O4 nanostructure with a spherical morphology, which is supported on reduced graphene oxide sheets (rGO). The nanocomposite has been subjected to an investigation of its morphological, structural and electrochemical characteristics. This material exhibits promise for electrochemical water splitting due to its significant electroactive surface area, distinctive morphology and metal ions (M+) synergetic effect on its electrocatalytic performance. The nanostructure of TiCo2O4/rGO-has been observed to exhibit robust electrocatalytic activity, underscoring the significance of the present study. Additionally, presented are the enduring stability of the OER, along with the reduced overpotential (269 mV@10 mA cm−2), decreased Tafel slope (37.56 mV dec-1) with greater electrochemical active surface area. Our finding suggests that the TiCo2O4/rGO nanohybrid exhibited high electrocatalytic efficiency and can be utilized in diverse electrochemical applications.

Revolutionizing Glucose Monitoring: Enzyme-Free 2D-MoS2 Nanostructures for Ultra-Sensitive Glucose Sensors with Real-Time Health-Monitoring Capabilities.

The growing requirement for real-time monitoring of health factors such as heart rate, temperature, and blood glucose levels has resulted in an increase in demand for electrochemical sensors. This study focuses on enzyme-free glucose sensors based on 2D-MoS2 nanostructures explored by simple hydrothermal route. The 2D-MoS2 nanostructures were characterized by powder X-ray diffraction, energy-dispersive X-ray spectroscopy, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and XPS techniques and were immobilized at GCE to obtain MoS2-GCE interface. The fabricated interface was characterized by electrochemical impedance spectroscopy which shows less charge transfer resistance and demonstrated superior electrocatalytic properties of the modified surface. The sensing interface was applied for the detection of glucose using amperometry. The MoS2-GCE-sensing interface responded effectively as a nonenzymatic glucose sensor (NEGS) over a linearity range of 0.01-0.20 μM with a very low detection limit of 22.08 ng mL-1. This study demonstrates an easy method for developing a MoS2-GCE interface, providing a potential option for the construction of flexible and disposable nonenzymatic glucose sensors (NEGS). Moreover, the fabricated MoS2-GCE electrode precisely detected glucose molecules in real blood serum and urine samples of diabetic and nondiabetic persons. These findings suggest that 2D-MoS2 nanostructured materials show considerable promise as a possible option for hyperglycemia detection and therapy. Furthermore, the development of NEGS might create new prospects in the glucometer industry.

Effect of Nano Spinel Ferrites Co0.9Cu0.1Fe2O4 on Non-Isothermal Cold Crystallization Behaviours and Kinetics of Its Composites with Polylactic Acid.

Nanoparticles of spinel ferrites with a composition of Co0.9Cu0.1Fe2O4 (AM NPs) were effectively synthesized via a hydrothermal route. The structure of ferrite nanoparticles was characterized with X-ray diffraction, which showed a single cubic spinel phase. Energy-dispersive X-ray (EDX) spectroscopy and field emission-scanning electron microscopy (FE-SEM) were employed to analyse elemental composition and surface morphology, respectively. Moreover, the effects of the Co0.9Cu0.1Fe2O4 on the morphology of [PLA = polylactic acid] nanocomposites were examined through polarized light optical microscopy (POM) and X-ray diffraction (XRD). The thermal behaviours for tested samples were studied through [DSC = differential scanning calorimetry] and [TGA = thermal gravimetric analysis]. A great number of minor PLA spherulites were detected using POM in the presence of the Co0.9Cu0.1Fe2O4 ceramic magnetic nanoparticles (AM), increasing with AM nanoparticle contents. X-ray diffraction (XRD) analysis showed that the presence of nanoparticles led to an increase in the intensity of diffraction peaks. The DSC findings implied that the crystallization behaviours for the efficient PLA as well as its nanocomposites were affected by the addition of AM nanoparticles. They act as efficient nucleating agents because they shift the temperature of crystallization to a lower value. The Avrami models were used to analyse kinetics data. The experimental data were well described using the Avrami method for all samples tested. The addition of AM to the PLA matrix resulted in a decrease in the crystallization half-time t1/2 values, indicating a faster crystallization rate. TGA data showed that the occurrence of AM nanoparticles decreased the thermal stability of PLA.

Fabrication of 0D/2D CoFe2O4/CoFe LDH composite intruded within CNTs network as a high-performance electrocatalyst for oxygen evolution and hydrogen evolution reactions

Designing highly efficient and durable multicomponent heterostructured composites as catalytic materials for concomitant hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is highly desirable. Researchers all over the world are continuously working to develop such materials. Herein, CNTs wrapped CoFe2O4/CoFe LDH (CoF/CoFe LDH@CNTs) ternary composite is synthesized by hydrothermal and ultra-sonication routes. Numerous methods, including X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), electrical Mott-Schottky, and electrochemical impedance spectroscopy (EIS) are employed to study structure, morphology, flat band potential, and electrochemical properties of prepared samples. In terms of water splitting performance, CoF/CoFe LDH@CNTs composite showed predominant performance for both HER and OER activities, as compared to its analogs (CoF and CoF/CoFe LDH). Faster electron transfer is also exhibited by CoF/CoFe LDH@CNTs, as it possesses a lower Tafel slope. For OER, CoF/CoFe, LDH@CNTs require a small overpotential of 170 mV to reach a current density of 10 mA cm−2 in 1 M KOH, with a Tafel slope of 42 mV dec-1. Similarly, for HER an overpotential of 218 mV is required to drive 10 mA cm−2 with a small Tafel slope of 31 mV dec-1. Impedance studies show a small value of charge transfer resistance (Rct = 1.11 Ω) for CoF/CoFe, LDH@CNTs. Significant electrochemical performance for CoF/CoFe, LDH@CNTs for both half-reactions (OER and HER) is ascribed to the synergy among electrochemically active CoF and CoFe LDH, and a highly conductive network of CNTs. The present strategy improves the electrochemical performance of electrochemical systems relevant to energy applications.