UV-DRS Analysis Research Articles

The Photocatalytic Activity of TiO2 Nanotube Doped Zn for Methylene Blue Degradation

TiO2 nanotube (TiO2-NT) is one of the promising materials for photocatalytic water remediation. TiO2-NT doped Zn (Zn/TiO2-NT) is synthesized from P25 Degussa via one step hydrothermal method. From XRD and UV-DRS analysis, it showed that Zn as a doping material led to decrease band gap energy and decrease the crystallite size. The best results obtained was Zn/TiO2-NT with a crystallite size of 7.14 nm, and band gap energy value of 3.18 eV. Photocatalytic activity of Zn/TiO2-NT was also tested for photocatalytic activity of textile dye (methylene blue) degradation. During the photocatalytic activity for methylene blue degradation, the Zn/TiO2-NT shows higher activity compared to non-doped sample. The non-doped sample shows degradation activity of 87.72%, meanwhile the Zn/TiO2-NT shows degradation activity of 95.88%.

Synergistic effects of Co-Mn co-doping on the structural and optical properties of TiO2 nanospheres: Dual functions for DSSC photoanodes and degradation photocatalyst

Synthesizing direct solar irradiance-responsive nanomaterial capable of serving as an efficient photoanode for dye-sensitized solar cells (DSSCs) and active photocatalysts for organic pollutant elimination poses a formidable challenge. This study focused on the synthesis of cobalt and manganese co-doped titanium dioxide (TiO2) nanoparticles via sol-gel technique, enhancing their efficacy in both the DSSCs and methylene blue (MB) dye degradation. X-ray diffraction and Raman analysis confirm the existence of a tetragonal crystal structure with the anatase phase of TiO2, while XPS analysis verifies the successful integration of cobalt and manganese ions into the host lattices. BET analysis has confirmed that Co, Mn co-doped TiO2 exhibits a higher pore volume and specific surface area compared to the undoped TiO2 material. FESEM and HR-TEM reveals spherical shape morphology and EDS mapping confirms the purity of synthesized nanoparticles. Moreover, Co-Mn co-doped TiO2 nanoparticles exhibits a shift in the optical absorption edge towards the visible spectrum in UV-DRS analysis. PL analysis suggests a diminished electron-hole recombination within the doped and co-doped sample. Electrochemical impedance spectroscopy demonstrates improved charge transfer properties. DSSCs employing the co-doped TiO2 exhibit significantly enhanced power conversion efficiency (4.99 %) compared to bare TiO2 (2.03 %), cobalt-doped (2.61 %), and manganese-doped TiO2 (3.97 %). Additionally, it demonstrates exceptional photocatalytic activity, with 87.83 % (Co-Mn co-doped TiO2) degradation efficiency with a lesser time extent for the methylene blue dye degradation. These findings underscore the potential of Co-Mn co-doped TiO2 for addressing dual challenges in renewable energy (DSSC) and environmental remediation (Pollutant removal).

Impact on bandgap, electrical and magnetic properties of SnO2 nanoparticles by cerium and samarium

Synthesis of undoped, Samarium (Sm) and Cerium (Ce) co-doped SnO2 nanoparticles along with their enhancement in structural and physicochemical properties are reported. The samples have been prepared by co-precipitation method. The tetragonal rutile-type structure from PXRD pattern confirms the synthesized materials and obtained an average crystallite size of 23, 19 and 14 nm for the pure, 2 and 4 wt.% of Sm-Ce co-doped SnO2 NPs. The band at 620 cm−1 is assigned to the bonding of metal-oxygen as O-Sn-O bridging bond of SnO2 through FTIR-spectrum. From UV–DRS analysis, bandgap energy is found to be 3.45, 3.38 and 3.26 eV respectively for pure, 2 & 4 wt.% of Sm-Ce co-doped SnO2 NPs. Photoluminescence emission shows a sharp peak centered at 490 nm, a high intensity peaks at 521 and 538 nm due to blue and green emission. Addition of dopants narrowing the bandgap and reduces the dielectric constant as well as the dielectric loss. The dielectric constant and dielectric loss are directly proportional to temperature but inversely proportional to frequency, which shows that both polarizability and the method of charge transfer are impacted by the space charge polarization, which made the material could be a potential candidate in spintronics and high-performance dielectric materials. The effect of Sm-Ce co-dopants enhances the saturation magnetization value from 0.0049067 emu/g to 0.0072245 emu/g. The results exhibit that Sm-Ce (4 wt.%) co-doped SnO2 nanoparticles have strong dielectric and magnetic properties which is a potential candidate for spintronic devices.

Enhanced photocatalytic performance of CuS/O,N-CNT composite for solar-driven organic contaminant degradation

Herein, a hydrothermal etching approach was used to generate an innovative CuS/O,N-CNT composite. The hydrothermal etching of g-C3N4 led to the creation of O,N-CNT, with ethanol as the oxygen source. The SEM and TEM characterizations confirmed the formation of CNT, whereas the XPS analysis proved the doping of oxygen and nitrogen in the CNT matrix along with the incorporation of CuS. Under sun irradiation, the produced CuS/O,N-CNT showed outstanding photocatalytic efficiency, eliminating methyl orange and methylene blue dyes with 97.21% and 98.11% efficacy, respectively. Adding hydrothermally etched O,N-CNT increased light absorption and charge migration kinetics, as can be studied from the UV-DRS and PL analysis; hence, the observed improvements in light absorption and charge transfer pathways contributed to the CuS/O,N-CNT composite's enhanced photocatalytic activity, indicating its potential for efficient elimination of organic contaminants under solar irradiation. The catalyst demonstrated high reusability performance up to six cycles and significantly degraded other dyes. Scavenger analysis, along with VB-XPS and UV-DRS analysis, aid in developing a photocatalytic mechanism that confirms the participation of hydroxyl and superoxide radicals in the degradation process.

A Comprehensive Study of Cerium-Modified Bi2FeMnO6 Double Perovskite: Synthesis, Structure, Properties and Applications

This paper presents a detailed synthesis method by solid-state reaction route and typical characterization (structural, microstructural, dielectric, impedance, modulus, and optical properties) of a double perovskite material Bi2FeMn[Formula: see text]Ce[Formula: see text]O6. An orthorhombic crystal structure having an average crystallite size of 32.2[Formula: see text]nm is suggested by X-ray diffraction data (XRD). Scanning electron microscope (SEM) micrograph detects the presence of cylindrical nanorod-shaped distinct grains and well-defined grain boundaries in this material and the average grain size is 5.82[Formula: see text][Formula: see text]m. Furthermore, the purity and the presence of all constituent elements in the material were confirmed from energy dispersive X-ray (EDX) analysis and color mapping. Dielectric, impedance, modulus, and AC conductivity properties are studied within the temperature range of 25–500∘C and frequency range of 1[Formula: see text]kHz to 1[Formula: see text]MHz. The high dielectric constant at a low-frequency zone and low dielectric loss found in this material make it a promising candidate for better energy-storing devices. The negative temperature coefficient of resistance (NTCR) behavior is observed from the impedance study. The non-Debye relaxation is detected in the modulus study. The semiconducting nature of this material is verified by semicircular arcs observed in both Nyquist and Cole–Cole plots. The thermally activated conduction mechanism is confirmed by an AC conductivity study. The existence of Bi–O, Fe–O, Mn–O and Ce–O stretching vibrations are observed from the FTIR study and explain the presence of all constituent elements in the sample. The bandgap energy of 1.7[Formula: see text]eV is calculated from UV-DRS analysis and hence this material can be used for advanced optoelectronic and photovoltaic applications.

Zinc-modified barium stannate micro-rods: Investigating structural, morphological, and optical features

In the present study, we have synthesized pristine and Zn-doped (0.025, 0.05, 0.075, 0.10) barium stannate (BSO) micro-rods via the hydrothermal method. The prepared samples have been analyzed for their structural, optical, and morphological properties using X-ray diffraction technique (XRD), UV–Vis diffuse reflectance spectroscopy, field emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray spectroscopy (EDX). Our Rietveld refinement examination of the XRD data verifies that the samples are single-phase, with a cubic crystal structure. Additionally, the lattice parameters determined align closely with the existing literature. Furthermore, the FE-SEM analysis unveiled the presence of well-defined rod-shaped structures accompanied by particle agglomeration across the surface. Further, the EDX analysis confirmed the presence of key elements, providing crucial insights into the material's chemical makeup. Especially noteworthy was the UV-DRS analysis, demonstrating a direct correlation between increased Zn doping concentrations and a concurrent reduction in the band gap values. This adjustment aligns the material's band gap with those commonly found in key components utilized in DSSC and PSC cells, suggesting promising applications in these crucial technological domains.

Effect of TiO2/Fe2O3 nanopowder synthesis method on visible light photocatalytic degradation of reactive blue dye

Water pollution and scarcity of clean water are major issues of concern globally. In this study, titanium dioxide (TiO2) photocatalyst doped with ferric oxide (Fe2O3) was used to degrade reactive blue dye (171) using sunlight irradiation. Two approaches were employed to synthesize the photocatalyst: synthesis of ferric oxide and titanium precursor through ultrasonic-assisted sol-gel method and using iron (III) nitrate nonahydrate with commercial titanium dioxide. The photocatalysts were characterized using FTIR Spectroscopy, SEM, XRD analyses, and UVDRS to determine their chemical composition, morphology, crystallinity, and light absorption, respectively. The effect of contaminant concentration (1–3 ppm), solution pH and photocatalyst type on the degradation efficiency was studied. Doping enabled visible light absorption as confirmed by the UVDRS analysis. Solar photocatalytic degradation resulted in complete (100 % removal) of the dye within 2 h under solar irradiation for all concentrations of the dye studied. Furthermore, the photocatalysts exhibited superior performance in both neutral and acidic solutions compared to basic ones. After four cycles, the dye removal efficiency has decreased by less than 15 % for all the photocatalysts confirming the significant activity and high stability of the nanocomposite. The increased dye photodegradation efficacy of Fe2O3 doped TiO2 under sunlight irradiation is attributed to the narrowing of the photocatalyst's bandgap from 3.76 eV (in pure TiO2) to 2.83 eV. This narrowing of the bandgap enhances the absorption of visible light from sunlight, thus making this photocatalyst effective under sunlight and eliminating the use of electricity which is a requirement for ultraviolet photocatalysis.

Enhanced solar light-induced performance of a step-scheme heterojunction nanostructure (C3N4/ZrO2) for mixed dye degradation and methanol oxidation

This study focuses on the high demand for innovative nanostructured materials with boosted photocatalytic performance for the degradation of organic pollutants and oxidation of organic compounds. A nanostructure consisting of graphitic carbon nitride (C3N4) and zirconium oxide (ZrO2) denoted as C3N4/ZrO was synthesized via direct thermal pyrolysis. A comprehensive array of characterization techniques (XRD, FESEM, HRTEM and UV-DRs analysis) was utilized for a detailed analysis of the prepared photocatalysts. The photoactivity of the C3N4/ZrO nanostructure was explored by the photocatalytic degradation of a mixture of dyes (Rh B + CV), and methanol oxidation reaction and compared with those of pristine C3N4 and ZrO2. The photoactivity of C3N4/ZrO for degrading the mixed dye under simulated solar light was 97% higher than those of pristine C3N4 (88%) and ZrO2 (31%). The C3N4/ZrO nanostructure, functioning as a step-scheme heterojunction, demonstrated superior photocatalytic performance due to enhanced charge transport facilitated by robust interfacial contact between C3N4 and ZrO2. This enhanced photodegradation efficiency, reaching 97%, establishes a foundation for the development of heterojunction catalysts with exceptional photocatalytic activities. Furthermore, the methanol oxidation activity of the C3N4/ZrO nanostructure was exceptionally high, yielding a 138.25 mA/cm2 current density at a 2 M methanol. The proposed material has a high application potential for mitigating pollution and energy issues.

Phenol degradation on the surface of mesoporous TiO2 particles via ligand-to-metal charge transfer under visible light irradiation

Degradation behaviors of phenol from aqueous solution under the blue light irradiation were studied using a series of sol–gel prepared TiO2 particles exhibiting different blue light absorbing abilities. The phenol degradation under the blue light irradiation was most pronounced in the presence of TiO2 sample exhibiting the lowest blue light absorbing ability among the samples, showing no correlations between phenol degradation and light absorbing ability of TiO2 particles. UV-DRS analysis and scavenging experiments revealed that phenol degradation under visible light irradiation can be majorly proceed via the light absorption by the ligand-to-metal-charge-transfer (LMCT).

Photocatalytic degradation of ciprofloxacin by using tannin-doped BaTiO3 catalyst

The aim of this study is to highlight the significance of ciprofloxacin degradation, a commonly used antibiotic in healthcare and agriculture, by synthesizing tannin-doped BaTiO3 (T-Ba) photocatalysts at various tannin amounts (0–50 wt%) and investigating their photocatalytic activity under both UV-A light and visible light irradiation. The impact of several parameters, including the initial concentration of ciprofloxacin, photocatalyst dosage, initial solution pH, and scavengers effect, on the photocatalytic activity was explored. The photocatalysts were characterized by FTIR, SEM, XRD, XPS, TEM, BET, PL and UV-DRS analysis. In the conducted studies, it was observed that the highest efficiency was achieved at 96 % under appropriate parameters. The kinetic study was conducted based on the Langmuir-Hinshelwood equations. According to stability tests, ciprofloxacin degradation was found as 92 % after the second cycle, while it was 50 % after the fifth cycle.

Eco-benign synthesis of α-Fe2O3 mediated Trachyspermum ammi: A new insight to photocatalytic and bio-medical applications

Environmental contaminants are a golabl concern, and even at very low quantities, they can be extremely harmful to the aquatic ecosystem. Microbial resistance and photocatalysis are popular strategies for removing hazardous substances from the environment. The present study developed the green synthesis of α-Fe2O3 nanoparticles from Trachyspermum ammi plant leaf extract. The crystalline and structural stability of green synthesized α-Fe2O3 nanoparticles were studied by XRD. The surface morphology was investigated by TEM and FESEM equipped with EDX analysis. Metal, oxygen bond (Fe-O) and their interaction on the surfaces and their valency were explored from FTIR and XPS spectra. Optical orientations and electron movements were revealed from UV-DRS analysis. Visible light photocatalytic methylene blue degradation confirmed the largest surface area, rate of recombination, photo-excited charge carriers, photo-sensitivity range and radical generations of α-Fe2O3 nanoparticles. The green synthesized α-Fe2O3 nanoparticles bacterial susceptibility was examined by the well diffusion method using (10, 20, 50, 100) µg/L concentration of nanoparticles. The antibacterial activity enhanced with the higher concentration of α-Fe2O3 (100 µg/L). The gram-negative bacteria of E.coli has high bacterial susceptibility on α-Fe2O3 nanoparticles. The reactive oxygen species and OH radicals of α-Fe2O3 nanoparticles are demonstrated better resistivity against bacterial strains. The present study, therefore, suggested that the green synthesis would be an appropriate approach to synthesize the nanomaterials and confirming their suitability for use in industrial wastewater treatment and biomedical applications.

Synthesis and characterization of Fe3O4/SiO2/Alginate photocatalyst from tin tailings for batik cual waste degradation

Fe3O4/SiO2/Alginate as photocatalyst for degradation of Batik Cual Waste has been synthesized. This study aimed to determine the degradation of cual batik waste using Fe3O4/SiO2/Alginate photocatalyst assisted by UV-C light. In this research, Fe3O4 was synthesized through the coprecipitation method, then coated with SiO2 and sodium alginate The source of SiO2 used comes from tin tailings sand. SiO2 content in tin tailings is 87.45%. UV DRS analysis showed that the band gap energies of SiO2, Fe3O4, Fe3O4/SiO2, Fe3O4/SiO2/Alginate were 1.76 eV, 1.61 eV, 2.04 eV and 1.59 eV, respectively. XRD analysis showed that the Fe3O4/SiO2 composite was successfully formed in the presence of typical diffraction peaks for silica quartz and magnetite on the composite diffractogram. Based on the percent degradation data, it was obtained that the optimal degradation time using the Fe3O4/SiO2/Alginate composite was 96.73% at 30 minutes.

The exploitation of plant wastes in ZnO photocatalyst electrosynthesis for 2,4-dichlorophenol degradation application

ZnO is established as an efficient photocatalyst for pollutant degradation but, its synthesis process that involves hazardous chemicals becomes a limitation. This work, therefore, proposed a green ZnO electrosynthesis strategy utilizing banana peel (BP) and tea leaf residue (TLR) extract. The generated ZnO photocatalysts were characterized via FTIR, SEM, XRD, BET, PSA, XPS, HRTEM and UV-DRS analysis and subjected to 2,4-dichlorophenol degradation for photocatalytic activity evaluations. The findings revealed that the ZnO-TLR sample contributed to the highest 2,4-dichlorophenol degradation (88.5%) followed by ZnO-BP (76.2%) and ZnO commercial (62.1%). This can be associated with the narrower band gap (3.20 eV), intense FTIR band of Zn-O bonds, larger surface area (9.576 m²/g), uniform surface morphology, and oxygen vacancies existence of ZnO-TLR. The highest amount of phenolic content, flavonoid content, and reducing power capacity of TLR extract as obtained by preliminary phytochemical assays was believed to contribute to such properties. The optimum reaction conditions were then found to be pH 3, 30 ppm 2,4-DCP, and 0.01 g catalyst with maximum 91.2% degradation. The ZnO-TLR catalyst was reusable for up to 3 cycles with a final 79.0% degradation. The kinetic study revealed that the photodegradation reaction that occurred in this work obeyed the pseudo-first-order kinetic model. It was found that the photogenerated hole was the main oxidation species in the 2,4-dichlorophenol mineralization process in this work.

Synergistic effect of energy filtering, modulation doping and boundary scattering of multiphase Cu-Sb-Bi-S system for enhanced thermoelectric performance

In this a multiphase cubic system has been successfully synthesised by solvothermal method. The profile fitting using Rietveld refinement confirms the phase fraction of monoclinic-Cu4Bi5S10, orthorhombic-Cu3BiS3, orthorhombic-Sb2S3 and tetragonal- Cu3SbS4 as 54.56%, 40.33%, 2.96%, 2.15%, respectively. Further, the presence of multiphase was additionally confirmed using HR-TEM analysis from observing the various patterns of atomic arrangement in the lattice plane. Moreover, a narrow band gap of 0.64 eV was confirmed using UV-DRS analysis. Electrical transport properties such as the Seebeck coefficient and electrical conductivity has been determined using ZEM-3 measurement which depicts the negative value of the Seebeck coefficient that conforms to the negative charge carrier transport. Interestingly the very low thermal conductivity of 0.37 Wm−1K−1 at 303 K is observed for the S2 sample. Overall, with enhanced electrical conductivity of 59.7 S.cm−1 at 473 K, and Seebeck coefficient of 60.3 μVK−1 at 353 K leads to a maximum ZT of 0.0068 at 473 K, which is due to the synergistic effects of boundary phonon scattering, energy filtering and modulation doping effect in the multiphase Cu-Bi-Sb-S system.

Insights into the Electrocatalytic Oxygen Evolution Reaction and Photocatalytic Methylene Blue Degradation of Mixed Spinel NixCu1–xFe2O4 Nanocomposites Anchored at Sulfur-Doped g-C3N4

In consideration of energy conversion and/or environmental protection, it is important to develop electrocatalytic and/or photocatalytic active materials for the oxygen evolution reaction (OER) and photodegradation of methylene blue (MB), respectively. To meet these requirements, mixed spinel ferrites such as NixCu1–xFe2O4 anchored at sulfur-doped graphitic carbon nitride (SCN) nanosheets was developed for the first time via a simple one-pot hydrothermal method for the construction of a novel bifunctional NixCu1–xFe2O4@SCN nanocomposite. Initially, the crystal structure, optical properties, surface morphology, elemental composition, and surface area of different nanocomposites, such as NiFe2O4, Ni0.8Cu0.2Fe2O4, Ni0.5Cu0.5Fe2O4, Ni0.2Cu0.8Fe2O4, SCN, and Ni0.5Cu0.5Fe2O4@SCN, were studied through XRD, UV-DRS analysis, FT-IR, FE-SEM with EDX, HR-TEM, and BET analysis. Furthermore, when compared to other prepared electrode nanocomposites such as spinel ferrites or different proportion mixed spinel ferrites, the Ni0.5Cu0.5Fe2O4@SCN nanocomposite loaded 316 SSL mesh electrode demonstrated exceptional electrocatalytic oxygen evolution performance with a very low overpotential of 250 mV at 10 mA cm–2 current density and outstanding stability. Subsequently, the photocatalytic activities of the prepared mixed spinel ferrites, NixCu1–xFe2O4@SCN nanocomposites, were tested through the degradation of MB under visible-light irradiation. Among the prepared photocatalysts, Ni0.5Cu0.5Fe2O4@SCN nanocomposite showed superior photocatalytic MB degradation under visible light, which is firmly due to the equi-proportion blending of Cu+2 substitutions in mixed spinel ferrites at SCN. Accordingly, the Ni0.5Cu0.5Fe2O4@SCN nanocomposite shows excellent photocatalytic degradation (POD) efficiency of 99.1% for MB in 40 min, while other nanocomposites such as NiFe2O4, SCN, and Ni0.5Cu0.5Fe2O4 show 40.2, 42.5, and 91.2% degradation efficiencies, respectively. Thus, the Ni0.5Cu0.5Fe2O4@SCN nanocomposite could be a promising material for electrocatalytic OER and/or photocatalytic degradation of MB under visible-light irradiation.

Design and synthesis of thiophene containing bis-chalcone-based mesoporous polymers for volatile iodine capture

Two novel thiophene-containing bis-chalcone-based polymers poly [(1E,4E)-1,5-Di-2-thienylpenta-1,4-dien-3-one] (PTCA) and poly[(1E,4E)-2,4-dimethyl-1,5-di(thiophen-2-yl)penta-1,4-dien-3-one] (PTCM) were designed and synthesized by FeCl3 mediated oxidative coupling polymerization reaction. The formation of polymers was confirmed by FT-IR and UV-DRS analysis, and the structural and morphological characterizations were done by PXRD, SEM, TEM, TGA, CHNS, and BET analysis techniques. Owing to their mesoporous nature, and excellent thermal and chemical stability, they found significant applications in the field of environmental remediation. Regardless of their low surface area, they emerged as strong candidates for the iodine capture process due to the presence of electron-rich heteroatoms. The maximum iodine capture capacity obtained for PTCA and PTCM were 242 and 221 wt.% respectively. The kinetic study revealed that the adsorption of iodine onto the polymers fit well in the pseudo-second-order kinetic model with a correlation coefficient R2 > 0.99, pointing to the chemisorptive nature of adsorption. The polymers can be competently recycled and reused even after five cycles without a significant loss of iodine uptake. After the first cycle, the iodine release efficiency was as high as 89% and 93% for PTCA and PTCM respectively. The iodine uptake capacity of the reused polymers PTCA and PTCM was found to be 89.2% and 86.5% respectively after five successive cycles. And these materials offer the benefits of facile, low-cost, large-scale, and template-free synthesis of mesoporous polymers. This study also provides an opportunity for the design same kind of polymers with different heteroatoms and functional groups.

The effect of metal-titania interaction on photodegradation in SBA-15-supported metal-titania photocatalysts

Several transition metals (Fe, Cu, Ni, Cr, and Co) were inserted into the Ti-SBA-15 using two-step synthesis methods. XRD, SEM-EDX, N2 adsorption-desorption isotherms, XRF, and UV-DRS analysis were used for characterizations. The results confirmed preserving an ordered mesoporous structure, well-dispersed Ti-metal and enhanced light absorption compared with Ti-SBA-15. The photocatalytic performances were evaluated in the degradation of methylene blue under UV light. The results show that the Co-Ti-SBA-15 exhibited the highest photocatalytic activity among the prepared photocatalysts for the degradation of methylene blue. The significant activity increase might be attributed to the increased reactant adsorption by the mesoporous structure of SBA-15, the good distribution of TiO2 in the pores of SBA-15, and the increased electron transfer mobility due to metal doping. In addition to efficiency, Co-Ti-SBA-15 is a suitable catalyst for dye degradation, exhibiting good stability in methylene blue degradation over five photocatalytic runs without any deviation of the structure.

Novel synthesis of Cu2ZnAl2O4 nanostructures for photocatalytic and electrochemical sensor applications

Hybrid nanostructured materials currently offer a potential approach for a variety of applications due to improvements in their physio-chemical characteristics. Techniques for XRD, TEM-HRTEM, SAED, and UV-DRS were used to characterize the Cu2ZnAl2O4 (CZA) material. Without any secondary phases and with an average crystallite size of 40 ​nm, X-ray diffraction pattern examination demonstrates the increased crystalline structure. A highly crystalline, polydisperse CZA nanostructure was visible using TEM-HRTEM and SAED. The CZA nanostructure's light-absorbing behavior is presented by UV-DRS analysis, which found that the predicted bandgap energy was 5.0 ​eV. In this article, we describe an easy chemical synthesis of a hybrid CZA nanostructure that works well as a catalyst to break down the acid red 88 (AR-88) dye under UV, sunlight, and low light conditions. Additionally, it was studied to determine how to modify the working electrode's surface to enable the detection of lead and tin metal ions. With 93.1% of degradation and comparison work on decolorizing AR-88 dye in the presence of both sunlight and darkness, CZA nanostructure was looked at as a potential catalyst for the decolorization of AR-88 dye. By using graphite electrode paste and cyclic voltammetry to analyze the synthesized sample in 1 ​N KCl, it was discovered that it had outstanding redox reaction and lead and tin detection capabilities.

Antibacterial, Antioxidant, Larvicidal and Anticancer Activities of Silver Nanoparticles Synthesized Using Extracts from Fruits of Lagerstroemia speciose and Flowers of Couroupita guianensis.

The present study aimed to analyze the in vitro antibacterial, antioxidant, larvicidal and cytotoxicity properties of green synthesized silver nanoparticles (Ag NPs) using aqueous extracts from fruits of Lagerstroemia speciosa and flowers of Couropita guinensis. Synthesized Ag NPs were characterized using UV-DRS, FTIR, XRD, DLS, and High-Resolution SEM and TEM analyses. Absorption wavelength was observed at 386 nm by UV-DRS analysis and energy band gap was calculated as 3.24 eV. FTIR analysis showed the existence of various functional groups in the aqueous extract and in the NPs. DLS analysis showed the stability and particle size of the synthesized Ag NPs. SEM analysis revealed that Ag NPs are in a face centered cubic symmetry and spherical shape with a size of 23.9 nm. TEM analysis showed particle size as 29.90 nm. Ag NPs showed antibacterial activity against both Gram-positive and Gram-negative bacteria. DPPH scavenging trait of Ag NPs was ranging from 20.0 ± 0.2% to 62.4 ± 0.3% and observed significant larvicidal activity (LC50 at 0.742 ppm and LC90 at 6.061 ppm) against Culex quinquefasciatus. In vitro cytotoxicity activity of Ag NPs was also tested against human breast cancer (MCF-7) and fibroblast cells (L-929) and found that cells viabilities are ranging (500 to 25 µg/mL) from 52.5 ± 0.4 to 94.0 ± 0.7% and 53.6 ± 0.5 to 90.1 ± 0.8%, respectively. The synthesized Ag NPs have the potential to be used in the various biomedical applications.

Design of SnO2 nanorods/polypyrrole nanocomposite photocatalysts for photocatalytic activity towards various organic pollutants under the visible light irradiation

A composite photocatalyst consisting of polypyrrole (PPy) and tin oxide (SnO2) was successfully synthesized via facile hydrothermal route and followed by a polymerization method. The as-prepared SnO2/PPy nanocomposite was characterized and confirmed by various analytical techniques such as XRD, Raman, UV-DRS, SEM, TEM, BET and EDAX analysis. The photocatalytic activity of SnO2/PPy composite was studied experimentally for the degradation of Reactive Black 31 (RB 31) and 4-chlorophenol (4-CP) dyes under simulated visible light irradiation at ambient conditions. It was indicated that the photocatalytic rate constant of ZnO/PPy was nearly 2 times higher than that of SnO2. Morover, the optimized SnO2/PPy (10 wt% SnO2 in PPy) photocatalyst shows degradation efficiency of 89 and 98% for RB31 and 4-CP dyes, respectively. Meanwhile, the SnO2/PPy nanocomposite charge transfer mechanism was investigated through photocurrent and impedance analysis. This work demonstrates that a simple ultrasonic method efficiently utilized for the preparation of nanocomposite and its applications.