As-synthesized Nanocomposites Research Articles

Enhancement in the optical and carbon dioxide gas sensing properties of polythiophene by dispersion of manganese dioxide nanoparticles

The present research article demonstrates the dispersion of manganese dioxide (MnO2) nanoparticles in polythiophene (PTh) to enhance the optical and gas sensing properties of PTh/MnO2 nanocomposites. The structural aspects of the as-synthesized nanocomposites were demonstrated by the techniques such as X-ray diffraction (XRD), Fourier transmission infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FE-SEM). Furthermore, the optical characterization of the resulting composite was investigated using UV-Vis spectroscopy. UV-Vis analyses of obtained nanocomposite revealed a forbidden band of ∼ 3.7 eV. The prepared nanocomposites were exposed to CO2 gas to investigate the composites suitability for gas sensing application, which prove to be promising materials. The prominent exploit of the present work is that 0.8 Wt.% MnO2 loaded PTh composite material exhibits significant sensing response at low operating temperature including good stability and fast response and recovery time. The core objective of this work is the discussion of the enhancement in stability, response and recovery time as a consequence of the interaction between the CO2 gas and the as-synthesized nanocomposites.

Electrochemical analysis of hydrothermally synthesized 2D/1D WS2/WO3 nanocomposites for solar cell application

The nanocomposites of transition metal dichalcogenides (TMDs) and metal oxides (MOs) show enhanced properties for photovoltaic applications. In view of this, we have reported the synthesis of a series of tungsten sulphide/tungsten oxide (WS2/WO3) nanocomposites, wherein tungsten to sulphur ratio has been gradually varied to achieve the optimized properties for photovoltaic applications. The samples were analysed for structural, optical, morphological, microstructural, electrokinetic and electrochemical properties by various characterization techniques. Integrating the properties of WS2 and WO3 provided enhanced properties in the form of wider absorbance range, optimized band gap, better colloidal stability and reduced charge transfer resistance. The as-synthesized nanocomposites showed the absorbance in UV & visible regions with the band gap varying from 1.54 eV to 1.68 eV. The zeta potential measurement showed high colloidal stability of some of the nanocomposites with values < −30 mV along with their uniform distribution. The electrochemical behaviour of the samples has been studied by cyclic voltammetry and potentio electrochemical impedance spectroscopy in which prominent redox peaks and diffusive behaviour have been observed. The impedimetric properties revealed the presence of Warburg diffusion which shows their suitability for photovoltaic applications. The sample with least sulphur to tungsten molar ratio was observed to have lowest charge transfer resistance and highest exchange current density of 198.8 μA. The samples with molar ratio nearly unity have high charge transfer resistance and low exchange current density. The present work reveals that the optical, electrokinetic and electrochemical properties of WS2/WO3 nanocomposites can be optimized for solar cell application by controlling the precursors’ concentration.

Enhanced performance of 1D rod shaped Zirconium (Zr) decorated over spherical shaped Zinc oxide (ZnO) nanostructures for NO2 gas

1D rod shaped Zirconium (Zr) was decorated over spherical shaped Zinc (ZnO) nanostructures, using hydrothermal technique. The as-synthesized nanocomposites were discovered to be discriminatory in terms of sensing nitrogen dioxide (NO2) gas. The impact of doping on structural parameters, optical properties, thermal stability, morphology, and shape were explored using HR-TEM, XRD, SAED, UV–Visible, FE-SEM, FT-IR, and EDS. The doping concentration was optimized for maximal reactivity with gas. ZZ@5 nanocomposites have the highest response (70.9 %) when compared to pure ZnO, ZZ@2, ZZ@7, ZZ@5, and ZZ@10 nanocomposites. NO2 gas reaction and recovery times were 24.5 and 27.8 s, respectively. As the concentration of NO2 gas climbs from 20 to 200 ppm, the reaction to gas sensors increases. NO2 gas has higher selectivity for ZZ@5 nanocomposite than other gases (ethanol, ammonia, hydrogen, carbon monoxide, and liquefied petroleum gas). The repeatability of ZZ@5 nanocomposite was researched for 50 days and discovered to be impressive.

Comparative evaluation of antimicrobial activity of spinel structured transition metal ferrites supported on reduced graphene oxide against pathogenic strains of bacteria and fungi.

One of the global challenges for living things is to provide pollution and harmful microbes-free environment. In this study, magnetically retrievable spinel-structured manganese zinc ferrite (Mn0.5Zn0.5Fe2O4) (MZF) was synthesized by a facile solvothermal method. Further, the MZF with different weight percentages (10wt%, 50wt%, and 80wt%) were supported on reduced graphene oxide (rGO). The phase purity and morphology of MZF and MZF/rGO nanocomposite were confirmed by X-ray diffraction technique and scanning electron microscopy, respectively. The Fourier transform infrared spectroscopy, Raman, UV-visible spectroscopy, and thermogravimetric analyses of the as-synthesized nanocomposites were examined for the detection of various chemical groups, band gap, and thermal properties, respectively. The MZF/rGO nanocomposite exhibited significant antibacterial and antifungal activity against Eggerthella lenta, Enterococcus faecalis, Klebsiella pneumonia, Pseudomonas aeruginosa, and Candida albicans compared to bare MZF and rGO. The high surface area of rGO plays a crucible role in antimicrobial analysis. Additionally, the anti-bacterial and fungal activity is compared by synthesizing various metal ferrites such as MnFe2O4, ZnFe2O4, and Fe3O4. The 50wt% MZF/rGO nanocomposite exhibits significantly high antibacterial activity. However, 10wt% MZF/rGO nanocomposite shows good antifungal activity than Fe3O4, MnFe2O4, ZnFe2O4, MnZnFe2O4, 50wt%, and 80wt% MZF/rGO nanocomposites. These findings suggest that the prepared ferrite nanocomposites hold promise for microbial inhibition.

Rational sonochemical engineering of Ag2CrO4/g-C3N4 heterojunction for eradicating RhB dye under full broad spectrum

In this novel research, S-scheme Ag2CrO4/g-C3N4 heterojunctions were generated by sonochemical hybridization of different compositions of Ag2CrO4 nanoparticles [EVB=+2.21 eV] and g-C3N4 sheets [ECB=-1.3 eV] for destructing RhB dye under artificial solar radiation. The as-synthesized nanocomposites were subjected to X-ray diffraction [XRD], diffuse reflectance spectrum [DRS], X-ray photoelectron spectroscopy [XPS], N2-adsorption-desorption isotherm, photoluminescence [PL] and high resolution transmission electron microscope [HRTEM] analysis to explore the interfacial interactions between g-C3N4 sheets and Ag2CrO4 nanoparticles. Spherical Ag2CrO4 nanoparticles deposited homogeneously on the wrinkles points of g-C3N4 sheets at nearly equidistant from each other facilitating the uniform absorption of solar radiations. The absorbability of solar radiations was enhanced by introducing 20 wt % Ag2CrO4 on g-C3N4 sheets. The surface area of g-C3N4 sheets was reduced from 37.5 to 16.4 m2/g and PL signal intensity diminished by 80 % implying the successful interfacial interaction between Ag2CrO4 nanoparticles and g-C3N4 sheets. The photocatalytic performance of heterojunctions containing 20% Ag2CrO4 and 80 % g-C3N4 destructed 96 % of RhB dye compared with 60 and 33 % removal on the surface of pristine g-C3N4 sheets and Ag2CrO4, respectively. Benzoquinone and ammonium oxalate are strongly scavenged the dye decomposition revealing the strong influence of valence band holes of Ag2CrO4 and superoxide radicals in destructing RhB dye under solar radiations. S-scheme charge transportation mechanism was suggested rather than type II heterojunction on the light of scavenger trapping experiments results and PL spectrum of terephthalic acid. Overall, this research work illustrated the manipulation of novel S-scheme heterojunction with efficient redox power for destructing various organic pollutants persisted in water resources.

2D g-CN@Ni-bpy MOF nano-composite for photocatalytic activity

Ni-bpy MOF and g-CN@Ni-bpy MOF composite were fabricated by a one-pot solvothermal technique. The morphological and elemental composition was put forward by the study of PXRD, FT-IR, XPS, FE-SEM, EDS, HRTEM and UV-DRS. The as-synthesized nano-composite was effectively utilized as catalyst for Z-scheme degradation of Malachite green dye under natural sunlight. The g-CN@Ni-bpy MOF nano-catalyst caused degradation of 97.7 % of the dye within 45 min without the aid of any further additives. Furthermore, the mechanism of Z- scheme degradation over g-CN@Ni-bpy MOF was also investigated. From all this, it can be concluded that g-CN@Ni-bpy MOF is a potential catalyst for wastewater remediation.

Preparation and Spectrochemical characterization of Ni-doped ZnS nanocomposite for effective removal of emerging contaminants and hydrogen Production: Reaction Kinetics, mechanistic insights

In this study, we report the successful synthesis of Ni-doped ZnS nanocomposite via a green route using ethanolic crude extract of Avena fatua. The as-synthesized nanocomposite was comprehensively characterized using Dynamic light scattering (DLS), Zeta potential, scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and Atomic force microscopy (AFM). These analyses provided detailed insights into the size, morphology, composition, surface properties, and structural characteristics of the nanocomposite. Subsequently, the synthesized nanocomposite was evaluated for their photocatalytic performance against the organic dye Methyl orange. Remarkably, the nanocomposite exhibited rapid and efficient degradation of Methyl orange, achieving 90 % degradation within only 30 min of irradiation under UV light. Moreover, the photocatalyst demonstrated an exceptional hydrogen production rate, reaching 167.73 µmolg-1h−1, which is approximately 4.5 times higher than that of its pristine counterparts. These findings highlight the significant potential of Ni-doped ZnS nanocomposite as highly efficient photocatalysts for wastewater treatment and hydrogen production applications.

Ni decorated three-dimension hierarchical pyramidal ZrO2–Al2O3 nanoporous sheets for methane production

ZrO2–Al2O3 nanocomposites were synthesized by a modified co-precipitation method and loaded with 5%Ni as catalysts for methane production via n-heptane cracking. The as-synthesized nanocomposites were characterized by several techniques such as XRD, N2 adsorption-desorption, XPS, TEM, SEM, AFM, TGA, DTG, NH3 -TPD and Raman analysis. The XRD results confirmed the synthesis of amorphous γ alumina and hexagonal phase of zirconium alumina oxide (Zr5Al3O0.5) solid solution. XRD and SEM analyses showed additional small size Related to monoclinic phase of ZrO2 particles loaded on the Al2O3 surface. BET analyses confirmed the ZrO2–Al2O3 formation in mesoporous sheets structure. TEM images of the neat alumina, 10 ZA and their corresponding Ni loaded samples (Ni@10 ZA) revealed well-defined 3D hierarchical pyramidal structures with a height about 200 nm. All catalysts under this study exhibited high tendency to favor methane production via n-heptane cracking. At higher reaction temperatures, Ni@10 ZA catalyst exhibited higher cracking activity compared to the other prepared catalysts under this investigation which confirmed by NH3 -TPD analysis. A promising yield of methane was achieved at about 88 % coupled with 94.71 % selectivity at reaction temperature of 400 °C. Herein, the data collected through this research work revealed that Ni@10 ZA is a promising candidate for methane production via n-heptane cracking.

Metal organic framework derived vanadium nitride anchored on nitrogen-doped carbon sheet as an efficient electrocatalyst for nitrogen reduction reaction

A metal organic framework-assisted annealing and nitriding method is employed to prepare a heterostructured nanocomposite incorporating VN nanoparticles with nitrogen-doped carbonaceous sheets as an earth-abundant catalyst of electrochemical nitrogen reduction reaction (ENRR). In this as-synthesized nanocomposite (VN@NC), nanosized VN particles with diameter of ∼50 nm are in situ fabricated and are anchored on the metal organic frameworks-derived nitrogen-doped carbon sheets. Benefitting from its structural merits such as increased surface areas, abundant active sites, improved electroconductivity as well as the synergism between the components, the composite electrocatalyst exhibits a greatly enhanced catalytic activity for ENRR in comparison with the commercial bulk VN. The as-prepared VN@NC can catalyze nitrogen to yield ammonia with a rate up to 17.31 μg mg−1cat h−1 at a low potential (-0.2 V vs RHE) in 0.1 M hydrochloric acid solution under mild conditions, delivering a Faradaic efficiency of 10.99 % simultaneously. Furthermore, VN@NC also demonstrates a favourable selectivity without generation of hydrazine byproduct and a stable electrocatalytic performance.

Phytoassisted synthesis of CuO and Ag–CuO nanocomposite, characterization, chemical sensing of ammonia, degradation of methylene blue

The elimination of hazardous industrial pollutants from aqueous solutions is an emerging area of scientific research and a worldwide problem. An efficient catalyst, Ag–CuO was synthesized for the degradation of methylene blue, the chemical sensing of ammonia. A simple novel synthetic method was reported in which new plant material Capparis decidua was used for the reduction and stabilization of the synthesized nanocatalyst. A Varying amount of Ag was doped into CuO to optimize the best catalyst that met the required objectives. Through this, the Ag–CuO nanocomposite was characterized by XRD, SEM, HR-TEM, EDX, and FTIR techniques. The mechanism of increased catalytic activity with Ag doping involves the formation of charge sink and suppression of drop back probability of charge from conduction to valance band. Herein, 2.7 mol % Ag–CuO exhibited better catalytic activities and it was used through subsequent catalytic experiments. The experimental conditions such as pH, catalyst dose, analyte initial concentration, and contact time were optimized. The as-synthesized nanocomposite demonstrates an excellent degradation efficacy of MB which is 97% at pH 9. More interestingly, the as-synthesized catalyst was successfully applied for the chemical sensing of ammonia even at very low concentrations. The lower limit of detection (LLOD) also called analytic sensitivity was calculated for ammonia sensing and found to be 1.37 ppm.

Process Optimization and Equilibrium, Thermodynamic, and Kinetic Modeling of Toxic Congo Red Dye Adsorption from Aqueous Solutions Using a Copper Ferrite Nanocomposite Adsorbent.

In the present investigation of copper ferrite, a CuFe2O4 nanocomposite adsorbent was synthesized using the sol-gel method, and its relevance in the adsorptive elimination of the toxic Congo red (CR) aqueous phase was examined. A variety of structural methods were used to analyze the CuFe2O4 nanocomposite; the as-synthesized nanocomposite had agglomerated clusters with a porous, irregular, rough surface that could be seen using FE-SEM, and it also contained carbon (23.47%), oxygen (44.31%), copper (10.21%), and iron (22.01%) in its elemental composition by weight. Experiments were designed to achieve the most optimized system through the utilization of a central composite design (CCD). The highest uptake of CR dye at equilibrium occurred when the initial pH value was 5.5, the adsorbate concentration was 125 mg/L, and the adsorbent dosage was 3.5 g/L. Kinetic studies were conducted, and they showed that the adsorption process followed a pseudo-second-order (PSO) model (regression coefficient, R2 = 0.9998), suggesting a chemisorption mechanism, and the overall reaction rate was governed by both the film and pore diffusion of adsorbate molecules. The process through which dye molecules were taken up onto the particle surface revealed interactions involving electrostatic forces, hydrogen bonding, and pore filling. According to isotherm studies, the equilibrium data exhibited strong agreement with the Langmuir model (R2 = 0.9989), demonstrating a maximum monolayer adsorption capacity (qmax) of 64.72 mg/g at pH 6 and 302 K. Considering the obtained negative ΔG and positive ΔHads and ΔSads values across all tested temperatures in the thermodynamic investigations, it was confirmed that the adsorption process was characterized as endothermic, spontaneous, and feasible, with an increased level of randomness. The CuFe2O4 adsorbent developed in this study is anticipated to find extensive application in effluent treatment, owing to its excellent reusability and remarkable capability to effectively remove CR in comparison to other adsorbents.

Introduction of TbFeO3/TbCoO3 as a visible-active heterojunction nanocomposite: Facile synthesis and characterization with an environment-lover approach

A facile sol-gel method was used to synthesize an innovative nanocomposite containing Terbium orthoferrite (TbFeO3) and Terbium orthocobaltite (TbFeO3) with olive and Vitex agnus-castus leaves as natural reduction agents. The desired product comprised of two perovskites, TbFeO3 and TbCoO3, was utilized to degrade two anionic and cationic dyes after optimizing the synthesis conditions. A better photocatalytic efficiency in acidic media may be achieved as a result of the better performance of this nanocomposite for degradation of anionic dye. Also, the two other reactions were performed separately in order to synthesize each of the components of the as-synthesized nanocomposites. A couple of three-component nanocomposites with fascinating properties were produced as a result of this experiment. As a result of optical studies, different patterns of charge carrier transfer were assumed for them, which contributed to the theoretical creation of heterojunction photocatalysts with a variety of configurations. A summary of the results shows that the maximum degradation percentage of Eriochrom Black T during 90 min under visible light in pH = 5 in the presence of as-prepared was 91.7. This two-component nanocomposite demonstrated a type I configuration for charge carrier transfer.

Development of octahedral shaped Zn2TiO4 loaded Ti3C2-TiO2 ternary composite with excellent photocatalytic efficiency

The development of highly efficient and stable earth-abundant photoanode materials for photoelectrochemical water splitting is crucial for a sustainable energy economy. Being earth-abundant, 2D Ti3C2 MXenes have recently emerged as promising candidate for efficient photocatalytic performances. However, pristine Ti3C2and its composites suffer from poor electron–hole separation and fail to prevent the spontaneous recombination process due to the poor conductivity derived from the serious agglomeration of MXene sheets during processing. Therefore, suitable heterojunction engineering of the MXene based composites is required for their efficient photocatalytic performances. Hence, in this work, we have developed a Ti3C2-TiO2 and octahedron-shaped, nanosized Zinc titanate (Zn2TiO4) based ternary nanocomposite with optimized composition via a simple process of alkalization followed by hydrothermal. As-synthesized Ti3C2-TiO2/Zn2TiO4 (1:0.5) nanocomposite shows a 3.7 fold augmentation in photocurrent density as compared to alkali treated Ti3C2-TiO2 at a potential of 0.9 V vs Ag/AgCl resulted due to the facile charge transfer evidenced from its impedance analysis having lowest charge transfer resistance. Furthermore, the Mott-Schottky measurements reveal that the as-synthesized nanocomposites possess n-type semiconductivity and the charge carrier concentration of Ti3C2-TiO2/Zn2TiO4 (1:0.5) is almost 5.2 times higher than that of alkali-treated Ti3C2-TiO2. This work may inspire more excellent work on developing MXenes-based photoanodes.

Facile synthesis of nanostructured sodium and MoS2 incorporated Ni-MOFs with excellent cyclic durability for symmetric supercapacitor application

Highly porous and nanostructured metal-organic frameworks (MOFs) have fascinated enormous interest as electrode active materials for electrochemical energy storage systems, whereas their practical applications are significantly hindered by their relative inferior energy density and cyclability. In this study, MoS2 with layered structure was successfully incorporated onto hierarchical Ni-MOFs via a facile hydrothermal approach. Moreover, sodium cations were introduced to improve electronic conductivity. The resulting nanocomposites (sodium ions and MoS2 incorporated Ni-MOFs) exhibited hierarchical porous structures with varying dimensions, offering increased volume for charge storage and diffusion channels for electrolyte ions. Benefiting from the unique topological architectures, the as-synthesized porous nanocomposites delivered an excellent supercapacitive performance, achieving a superlative energy of 33.33 Wh kg−1 and a power density of 3390 W kg−1. Furthermore, the as-fabricated symmetric supercapacitor device delivered a remarkable cycling durability where the acquired outstanding capacitance retention was 97.42% and coulombic efficiency was 97.82% respectively over more than 10,000 cycles in an aqueous electrolyte.

Synthesis and Characterization of Ag/CdO Nanocomposite for the Photocatalytic Degradation of Methyl Orange Dye

Well crystalline Ag/CdO nanocomposite has been synthesized via the solution combustion synthesis (SCS) route. The Ag/CdO nanocomposite has been characterized in term of X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Raman spectroscopy. The crystallinity of the as-synthesized nanocomposite was obtained by using XRD technique. The crystallite size of the nanocomposite was calculated by the Scherrer equation and was found to be 47 nm. The surface morphology was obtained by FESEM spectroscopy. The particles appear to be porous in nature and wool-like morphology was obtained. Raman band at about 278 cm[Formula: see text] is because of the combination of transverse acoustic and optical phonon modes of cadmium oxide (CdO). Further, the Ag/CdO nanocomposite was used as a photocatalyst for the degradation of methyl orange (MO) dye. Results revealed that the photocatalytic activity of Ag/CdO nanocomposite for the degradation of MO dye increases with increasing the amount of photocatalyst. The rate constant, [Formula: see text] values for 100 mg, 150 mg and 200 mg of photocatalyst were 0.83, 2.21 × 10[Formula: see text] min[Formula: see text] and 3.81 × 10[Formula: see text] min[Formula: see text], respectively.

Novel mesoporous nanocomposite of WS2/ZIF-9 for efficient adsorption of textile dyes from wastewater

In this work, novel mesoporous nanocomposite of tungsten disulphide (WS2) and zeolite imidazole framework-9 (ZIF-9) has been successfully synthesized for the adsorption of carcinogenic textile dyes. Various characterization techniques revealed that the modification of WS2 nanosheets with ZIF-9, improved surface chemistry, textural properties, morphological features, surface area, and surface charge of synthesized nanocomposite. Field-Emission Scanning Electron Microscopy (FESEM) and High-Resolution Transmission Electron Microscopy (HRTEM) were used for the morphological details and analysis of size of polyhedrons with diameter of (∼1030 nm), length of each side of polyhedron (∼580 nm) and area of polyhedron ∼ 750 µm2, uniformly distributed on the surface of WS2 nanosheets. The enhanced specific surface area (∼114 m2/g) and micropores of as-synthesized nanocomposite as compared to pristine samples were confirmed by using Brunauer-Emmett-Teller (BET) analysis. A comparative adsorption study was performed using cationic and anionic dyes for determining the adsorption efficiency of pristine WS2 and ZIF-9 (WZF) nanocomposite. The adsorption capacity of as-synthesized materials was studied as a function of concentrations (2, 3 and 5 mg) for Malachite Green (MG) and Crystal violet (CV), textile dyes. The obtained higher adsorption capacity of WZF nanocomposite for CV (∼2124 mg/g) than MG (∼911 mg/g) is due to more electrostatic interactions between CV molecules and adsorbent because of having higher nitrogen groups in CV as compared to MG. The attained higher adsorption efficiency for MG and CV using synthesized WZF nanocomposite as compared to the pristine WS2 was explained on the basis of optimized surface charge (zeta potential study), large specific surface area (BET analysis) and lower recombination rate (TRPL study). The point of zero charge (PZC) was also analyzed by zeta potential studies at diversified values of pH for understanding the adsorption mechanism. The Langmuir isotherm provides best fit for the adsorption process with high value of R2: 0.99 and 0.97 (∼1) for both MG and CV dyes, respectively. The efficiency achieved throughout the four cycles of reusability study confirms the stability and regeneration ability of materials. Such novel nanocomposite has not been previously reported and opens the new pathways to highly efficient, affordable and highly mesoporous material for wastewater treatment.

Popcorn-stick-like NH2-UiO-66/TiO2 nanotube nanocomposites toward optimized photocatalytic carbon oxidation with nitrogen dioxide

Developing photocatalytic technologies for pollutants removal with high harmless product selectivity is a significant challenge. Construction and optimization of nanocomposites junction with appropriate band alignments is an effective method for achieving this objective. Herein, a unique popcorn-stick-like NH2-UiO-66/TiO2 nanotube nanocomposites with staggered band alignment is fabricated. The small metal organic frameworks (MOFs) particles with diameters around 20 nm are uniformly dispersed on the surface of TiO2 nanoplates, creating a popcorn-stick-like structure. The resulting as-synthesized nanocomposites photocatalysts show distinguished photocatalytic activity for simultaneous removal of carbon particles and nitrogen dioxide with 100% NO2 conversion and 99% N2 selectivity, about 3.9 times higher than that of pristine TiO2. The significant enhancement is attributed to the rapid charge separation and transfer in TiO2 and NH2-UiO-66 interface and the visible light absorption. The enhanced charge transfer follows double charge transfer mechanism, which is confirmed by surface photovoltage spectroscopy, photoluminescence, transient photocurrent measurements, and electrochemical impedance spectroscopy. This study demonstrates the potential for the simultaneously removal of two pollutants using the composite of TiO2 and MOF materials with high surface area and visible light absorption ability, thereby providing the possible applications of NH2-UiO-66/TiO2 composites in environmental remediation including air purification and wastewater treatment.

Effect of Ag Doping on ZnO/V2O5 Nanoparticles as a Photo Catalyst for the Removal of Maxillion Blue (GRL) Dye

In this research, the photo catalytic degradation of textile dyes as a model Maxillion Blue (GRL) dye by using Ag/ZnO/V2O5 nanocomposites synthesised via hydrothermal method. The physical properties of the as-synthesised nanocomposites were examined using characterisation techniques such as scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), TEM, and UV-vis spectroscopy. the production of pure ZnO, V2O5 nanoparticles and the discovery, by XRD analysis, of diffraction peaks related to the hexagonal phase of ZnO, V2O5, UV-vis spectroscopic calculations of the nanocomposite’s energy bandgap (2.63 eV) indicated that it might function as a photo catalyst when exposed to UV-visible light. XRD also supported the fabrication of the ZnO/V2O5 nanocomposite. FE-SEM images showed that the object was spherical and somewhat hexagonal in form. EDX analysis reveals the presence of Zn, V, and O in the nanocomposite; its photocatalytic activity was evaluated through the degradation of GRL dye under exposure to solar light. The results showed that the optimum mass nanocomposite for efficient photo degradation was 0.4 g/L, with a degradation efficiency of 91.6%.

Encapsulation of amaranth CDs at ZIF-7 MOFs as a novel adsorbent for ultrasonic-assisted dispersive nano-solid-phase microextraction and ultrasensitive determination of allura red in food samples

Allura Red AC (AR) can be used in foodstuffs to give them a pleasant taste, color, appearance, stability, and smell. High consumption of the dye has been associated with adverse health effects. A sensitive method, namely ultrasound-assisted coupled dispersive nano solid-phase micro-extraction spectrophotometry (UA-DNSPME-UV–Vis) was designed for AR as food colorant preconcentration and determination in real samples. The method is based on the first-time usage of amaranth carbon dot@Zn (II) organic framework comprising benzimidazole (ZIF-7) composite. The characterization of the synthesized CD@MOF was performed using XRD, SEM, FTIR, HRTEM, EDX, SAED, UV–Vis absorption, and fluorescence. Among conventional parameters including pH, amount of sorbent, sonication time and type and volume of elution solvent was examined. The established method showed excellent linearity over the range of 0.30 – 7.00 nM. Anions and cations were also studied for their interference effect. The preconcentration factor was 85, with 0.60 nM LOD. As-synthesized nanocomposite had significant adsorption capacity and reusability. Analysis of some real samples showed satisfactory results in the range of 8.41 to 2953 mM for liquid food samples and from 2.95 to 5.88 mM for solid food samples with a satisfactory range of recovery values from 98.44 to 102.41 %.

Fabrication of LaFeO3-nitrogen deficient g-C3N4 composite for enhanced the photocatalytic degradation of RhB under sunlight irradiation

LaFeO3-nitrogen deficient g-C3N4 (LaFeO3-g-C3N4-H) heterostructure has been fabricated obtaining thermal polymerization of acetic acid-treated melamine followed by incorporation of perovskite-type LaFeO3 onto the graphitic carbon nitride nanosheets (g-C3N4) using La(NO3)3·6H2O and Fe(NO3)3·9H2O as precursors. The as-synthesized nanocomposite was investigated using Fourier Transform Infrared Spectroscopy (FT-IR), powder X-ray diffraction (XRD), UV–Vis Diffuse Reflection Spectroscopy (UV–Vis DRS), Scanning Electron microscope (SEM), and Transmission Electron microscope (TEM). The findings of the characterization study revealed the successful incorporation of LaFeO3 on g-C3N4-H nanosheets. The band gap energy of LaFeO3-g-C3N4-H heterojunctions was found to be active in the visible light region. The LaFeO3-g-C3N4-H ability to degrade Rhodamine B (RhB) dye in an aqueous solution was investigated under sunlight illumination. The results of photocatalytic degradation activity showed that LaFeO3-g-C3N4-H photocatalyst haspresented the highest photocatalytic efficiency of 99.5% after 60 min under sunlight irradiation. The remarkable photocatalytic activity can be attributed to the defect structure of g-C3N4 and the construction of heterojunction. In addition, LaFeO3-g-C3N4-H showed promise recyclability after 5 cycles with slight activity reduction.