UV-vis Absorption Studies Research Articles

Synthesis, Structure, and Non‐Linear Optical Properties of New Metal Semi‐Organic Complex: 1,4‐diazabicyclo[2.2.2]octane‐1,4‐diium tris(nitrato)‐silver

AbstractOptically transparent metal semi organic single crystal of 1,4‐diazabicyclo[2.2.2]octane‐1,4‐diium tris(nitrato)‐silver (DTNS) is synthesized using slow evaporation solution technique. This single crystal is grown with dimension up to using 1,4‐diazabicyclo[2.2.2]octane (DABCO) as solute and water and methanol as solvent in the presence metal salt silver nitrate. Single crystal X‐ray diffraction (XRD) study showed a trigonal structure with space group P3c1 and the sum formula . The composition of metal Silver (Ag) in single crystal is confirmed through Energy Dispersive X‐Ray Analysis. The confirmation of various functional groups in DTNS molecular structure is characterized by Fourier Transform Infrared Spectroscopy (FT‐IR). UV–Visible absorption study showed the cut‐off wavelength at 250 nm with transparency 350–700 nm and the bandgap is about 3.3 eV. The thermal stability and melting point temperature is analyzed by Thermogravimetry‐Differential Scanning Calorimetry (TG/DSC). The third order Non Linear Optics (NLO) efficiency of the synthesized crystal is times greater than that of KDP. All of these analysis implies that DTNS crystal can be beneficial element for non‐linear optical applications.

Deciphering the Influence of Zwitterionic Surfactants on Pluronic Co-assemblies: A Synergistic Odyssey through Spectroscopic, Microscopic, and Scattering Techniques.

Fundamental investigations into the photophysical properties and microenvironmental features of pluronic-zwitterionic surfactant mixed assemblies are essential for advancing our understanding of molecular interactions at the nanoscale, setting the stage for innovative solutions in drug delivery, diagnostics, and other applications of pluronic-zwitterionic surfactant assemblies. This investigation explores the intricate photophysics of pluronic-zwitterionic surfactant mixed assemblies, utilizing the twisted intramolecular charge transfer state forming styryl dye trans-2-[(4-dimethylamino) styryl] benzothiazole as a probe. By comparing the behaviors of two distinct poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) block copolymers with block composition of (PEO)132-(PPO)50-(PEO)132 [F108] and (PEO)100-(PPO)65-(PEO)100 [F127] at concentrations of 5 and 10 wt %, this study systematically examines the impact of the addition of zwitterionic surfactants. Through a comprehensive set of analytical techniques, including UV-visible absorption, steady-state emission, and time-resolved fluorescence emission studies, significant alterations in the emission spectra and quantum yields were observed upon the addition of zwitterionic surfactants. These modifications suggest a dynamic equilibrium for the transitioning of dye molecules between various microenvironments within the assemblies. Additionally, dynamic light scattering, zeta potential (ζ), nuclear Overhauser effect spectroscopy, small-angle neutron scattering, cryogenic transmission electron microscopy, field emission scanning electron microscopy, and fluorescence lifetime imaging microscopy analyses have shed light on the substantial impact of surfactant incorporation on the structural properties of assemblies.

Structure, Optical Properties and Magnetocaloric Effects in Gd3Fe5O12 Garnet Synthesized by Solid State Method

In this work, gadolinium iron garnet (Gd3Fe5O12) was synthesized using the solid-state ceramic method. The structural analysis, confirmed through Rietveld refinement, indicated the formation of a single-phase garnet structure. Scanning electron microscopy studies revealed uniform grain size and homogeneity in the sintered material, while UV-vis absorption studies showed a peak at 300 nm, indicating strong ultraviolet interaction and an optical band gap of 3.64 eV, suggesting optoelectronic potential. The fluorescence emission spectrum shows a band at 435 nm, while the excitation spectrum exhibits bands at 275 and 360 nm. The magnetic measurements demonstrated Gd ion ordering at low temperatures, with a compensation temperature around 290 K. Arrott plots confirmed the second-order magnetic phase transition. Importantly, Gd3Fe5O12 exhibited both normal and inverse magnetocaloric effects, with a maximum magnetic entropy change of 1.05 J kg–1 K–1 at 230 K under 9 T magnetic field. These properties indicate Gd3Fe5O12 material as a promising candidate for magnetic refrigeration and optoelectronic applications.

Integrating atmospheric water harvester with hydrovoltaics: Simultaneous freshwater production and power generation

Integrating an atmospheric water harvester (AWH) with hydrovoltaic (HV) technology pokes a new technology and notification to the arid region people to harvest freshwater and electricity simultaneously from the humid atmosphere even in the non-water region. In this work, we have fabricated a composite material by attaching the sulfonic groups to the graphitic oxide substrate (SGhO) through a one-step reflux method. The material delivers an excellent water absorbing ability of 0.3 g g−1h−1and 2 g g−1in 19 h under a 40–60 % humid environment. The electrical experiments show during moisture absorption, a specific voltage and current are generated indicating the dissociation of sulfonic groups in the graphitic structure creates a drift movement of H+ions through the composite. Our device delivers a voltage of 0.25 V and a high current of 160 µA from a single device during moisture movements through the structure under the relative humidity of 60–65 %. The rapid enhancement of the interfacial temperature from 31 °C to 44 °C within a minute due to the presence of graphitic oxide shows excellent photothermal capacity for the light-induced evaporation mechanism and collecting the condensed water as freshwater. The composite can evaporate all absorbed water within 0.5 h in one sun illumination (1 kW/m2) under the ambient relative humidity (RH) of 40–60 %. Several trials of washing treatments were done to ensure the chemical bonding of sulfonic groups into the graphitic structure. Therefore, it was confirmed the excellent stability, and repeatability for repeatable practical applications. Furthermore, the purity of the collected water is conducted with various analyses such as pH, TDS, and UV–Vis absorption studies and confirmed the excellent purified water which highly meets the global drinking water standards. Therefore, this work demonstrates a single way to achieve dual goals such as water harvesting as well as power generation for a better tomorrow.

Photocatalytic Degradation of Transition Metal (Ni) Doped ZnS Nanoparticles Synthesized via Simple Solvothermal Route

Ni doped ZnS nanoparticles were obtained using the simple Solvothermal Microwave Irradiation (SMI) method in this research. This technique is cost-effective and results in a high level of uniformity in particle size. The sample's structural characteristics were examined utilizing XRD Technique, FESEM image, Elemental analysis of the as prepared sample obtained from EDX spectrum and their optical characteristics analysed by using UV-Visible absorption study. The XRD pattern of Ni doped ZnS nanoparticles were to obtain their crystallite size (D), lattice constant (a), and volume of the unit cell (V). As the concentration of Ni dopant increased (0, 2.5, 5.0) M %, the values of the lattice constant decreased, leading to an overall decrease in the volume of the unit cell. FESEM images reveals the sample have uniform surface morphology and EDX analysis give evidence for element Zn, Ni, S presents in the sample. Ni doped ZnS nanoparticle dimension strongly influences their optical characteristics. The optical bandgap, as obtained from UV-Vis measurements, ranges from 3.54 eV to 3.50 eV with doping concentrations varying from 0 M% to 5.0 M% .This adjustment in optical properties suggests that Ni-doped ZnS nanoparticles have diverse applications in optoelectronics, sensors, UV detectors, and as an efficient photocatalyst for degrading pollutants in water. The efficiency of the degradation of Methylene Blue dye by Ni doped ZnS nanoparticles was found to be 75.19%.

Improved photocatalytic performance of cobalt doped ZnS decorated with graphene nanostructures under ultraviolet and visible light for efficient hydrogen production

Highly dispersed Cobalt doped ZnS nanostructures were successfully fabricated on the surfaces of graphene sheets via a simple hydrothermal method. X-ray diffraction (XRD), X-ray photocurrent spectroscopy (XPS), Raman spectroscopy (RS), Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM) were utilized to analyze the structural characteristics of the cobalt doped ZnS decorated with graphene CoxZn1-xS\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\rm Co}_x{\\rm Zn}_{1-x}{\\rm S}$$\\end{document} rGO nanostructures (NSs). UV-visible optical absorption (UV-vis) studies were conducted to investigate their optical properties. In laboratory studies utilizing water and visible light, the photocatalytic activity of CoxZn1-xS\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\rm Co}_x{\\rm Zn}_{1-x}S$$\\end{document}rGO NSs at (x = 0, 1, 2, 4 and 6 atm.%) were evaluated. Graphite Oxide (GO) was successfully transformed into sheets of graphene and CoxZn1-xSrGO\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\rm Co}_x{\\rm Zn}_{1-x}{\\rm S \\, rGO}$$\\end{document} NSs possessed a crystalline structure according to the findings of XRD, RS and FTIR analysis. SEM investigation showed graphene sheets enhanced with ZnS NSs possessed cuboidal, spheroidal form of structure and displayed a paper like appearance. UV-vis confirmed a noticeable rapid increase in transmittance along the UV wavelength area and confirmed a highly transparent NSs in the wavelength range of (180-800 nm). Calculations using density functional theory (DFT) revealed that the Co NSs have more negative conduction bands than ZnS, allowing for effective electron transfer from cobalt to ZnS and exhibiting a band gap decrease as Co content increased. The Co0.04Zn0.96S\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\rm Co}_{0.04}{\\rm Zn}_{0.96}S$$\\end{document} rGO NSs sample had the highest photocatalytic activity, measured at 7648.9μmolh-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$7648.9 \\, \\upmu {\\rm mol} \\, {\\rm h}^{-1}$$\\end{document}. A combination of improved dispersion properties, greater surface area, increased absorption and enhanced transfer of photogenerated electrons, CoxZn1-xS\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\rm Co}_x{\\rm Zn}_{1-x}S$$\\end{document} rGO NSs increased the photocatalytic hydrogen generation activity.

Synthesis, Characterization, Investigation of DNA Interactions and Biological Evaluation of Co(II), Ni(II), Cu(II) and Zn(II) Complexes with Newly Synthesized 2-methoxy 5-trifluoromethyl benzenamine Schiff Base.

The biologically active and thermally stable bivalent Co(II), Ni(II), Cu(II), and Zn(II) complexes (C1, C2, C3, and C4) of novel Schiff base ligand [(5-trifluoromethyl-2-methoxyphenylamino)methyl)-4,6-diiodophenol (L)] have been synthesized. The structural analysis of these complexes have been carried out by elemental analysis, 1H-NMR, FTIR, ESI mass, UV-visible, ESR, TGA techniques and magnetic measurements. The obtained results were confirmed as square planar geometry for Ni(II) and Cu(II) complexes, whereas octahedral geometry for Co(II) and Zn(II) complexes. The geometry optimized structures were developed by employing CHEM 3D software. The DNA binding interaction studies such as UV-vis absorption, viscosity, and fluorescence studies have been confirmed that the mode of binding of complexes with DNA is an intercalative binding. The DNA cleavage studies revealed that all the complexes are found to be potent to cleave the DNA into Form I & II. The in-vitro pathological studies of all the complexes against various microbial strains (Gram + and Gram -), revealed that Cu(II) complexes are more potent compared to other complexes and Schiff base. The anti diabetic activity studies revealed that the Cu(II) complex exhibited slightly higher activity than Co(II), Ni(II), and Zn(II) complexes. The results of antioxidant activity by DPPH method, suggested that the Cu(II) complex has higher activity and comparable with the standard compounds.

Rapid in-situ green synthesis and antibacterial properties of silver nanoparticles

In-situ green synthesis of silver nanoparticles (AgNPs) using hydroxypropyl-methylcellulose (HPMC) as a reducing and stabilizing agent is presented in this paper. A simple solution-casting method is used for preparing nanocomposite films. The reduction of silver ions to silver elementary particles was completed when the alkaline pH was maintained. The initial confirmation of AgNPs was visualized by the brown color of the prepared solution and later confirmed by the surface Plasmon resonance peak obtained from the UV–visible absorption study. X-ray diffraction measurement study revealed the crystalline nature of the AgNPs with FCC structure. The uniform distribution of AgNPs in the HPMC matrix is witnessed by Scanning electron microscope. The spherical shape of the prepared AgNPs is observed by transmission electron microscopic images with an average size of 11 nm. Dynamic light scattering experiment exposed the hydrodynamic size distribution and good stability of AgNPs. Thermogravimetric analysis showed high thermal stability of nanocomposites. Mechanical studies showed increased elongation at break and tensile strength of the prepared nanocomposites. Dielectric constant and dielectric loss were ascertained to decrease with an increase in frequency. Further, the antibacterial activity study showed an excellent activity of AgNPs in contrast to human bacterial pathogens viz.,Staphylococcus aureusandEscherichia coli.

Enhancing anticancer efficacy: xovoltib-loaded chitosan-tripolyphosphate nanoparticles for targeted drug delivery against MCF-7 breast cancer cells

ABSTRACT The objective of this study is to obtain precise medication delivery by combining the drug xovoltib with chitosan nanoparticles that are synthesized from the cuttlebone of sepia. The effectiveness of this drug delivery system will be evaluated by examining its ability to inhibit the growth of cancer cells using the MCF-7 cell line. This study synthesized chitosan from the cuttlebone of sepia and complexed it with Tri Polyphosphate to form Chitosan-Tri Poly phosphate-nanoparticles (CS-TPP-NPS) using the ionotropic gelation method. The UV-visible absorption study showed a strong characteristic band ranging between 200–800 nm. The 2θ value at 20.0 degrees and 20.63 degrees indicates the crystalline nature of CS-TPP-NPS loaded with xovoltib. HR-SEM image but the morphology of chitosan nanoparticles was magnified with a high voltage of 20,000 KV and observed as spherical, porous and smooth. The in vitro drug delivery of xovoltib-loaded CS-TPP was tested against MCF-7 which had lowered the cell viability rate at 300 µl/mL.

2-Amino-4-chlorophenol based Schiff base allied organosilatrane and its silica nanoparticles: Sensing of Cu(II) ion and urease inhibitory activity via spectroscopic and molecular docking study

In this manuscript, 2-amino-4-chlorophenol based Schiff base allied organosilatrane was synthesized using click silylation approach. Then, an astonishing movement was made by encapsulation of compound 5 over silica nanoparticles (Si-NPs) to synthesize hybrid silica nanoparticles acknowledged as AP-NPs and were characterized through various techniques. The colorimetric as well as UV–Vis absorption studies were carried out to recognize the sensing behavior of probes 5 and AP-NPs towards array of metal ions. The probes 5 and AP-NPs detected Cu2+ ion across wide range of other co-existent metal ions recommending highly selective nature. Further, the possible binding modes between ligand 5 and CuCl2 were inspected experimentally through FT-IR and also, approved theoretically by DFT. Moreover, the molecular docking studies were performed to rationalize the highly preferred modes of interaction of ligand 5 with active site of urease.

Electrical, optical, and structural studies of lithium tungstate-based-phosphate glasses and glass-ceramics

Cathode and electrolyte materials are key components of Li-ion batteries, which influence the safety and electrochemical characteristics. This study focuses on the development and characterization of glassy and glass–ceramic showing either ionic or mixed ionic-electronic conductivity, that can be used as electrolytes or cathodes, respectively, in energy storage devices. Homogenous glasses within the (30 + x)Li2WO4–(70-x)(45.5Li2O–54.5P2O5) system are produced using the melt quenching technique. Structural characterization via XRD and IR spectroscopy revealed diverse structural units. UV–visible absorption studies evaluated optical properties, while impedance spectroscopy measured electrical conductivity. Li2WO4 addition increased density, molar volume, and microhardness. Enhanced electrical conductivity was observed, notably reaching 3.22 × 10−6 (Ω−1 cm−1) at room temperature and 3.13 × 10−5 (Ω−1 cm−1) at 423 K. The richer Li2WO4 materials exhibited ionic conductivity associated to lower activation energy around 0.20 eV. Conductivity’s frequency dependency analysis suggested a correlated barrier hopping mechanism.

Synthesis, computational and UV–Vis absorption studies of novel sulfathiazole azo sulfonamides acting as potent antitubercular agents

In this work, we have reported the synthesis of unprecedented sulfonamide azo dyes 4(a-j) by the diazo-coupling reaction of sulfathiazole with various coupling components. Different spectroscopic techniques, like FT-IR, NMR (1H and 13C), and HRMS, were used to precisely assess the structures of the target molecules. The UV–Vis absorption study was conducted using variety of organic solvents. Quantum chemical calculations, geometrical optimization, and molecular electrostatic potential regions of all sulfathiazole azo colorants were explored using (DFT)/B3LYP method. The efficacy of the synthesized dyes in combatting M. tuberculosis was examined using the MABA assay; the derivatives 4c and 4h demonstrated promising activity with MIC of 1.56 µg/mL. Further, in silico molecular docking study was performed to elucidate the interactions with enoyl-ACP reductase. Target compounds were screened for their antimicrobial activity using the broth microdilution method against two gram-positive, two gram-negative bacterial strains, and a fungal strain. The cytotoxic potential of the active compounds was assessed using the MTT assay against the Vero cell line.

Investigation on the Drug Release Efficacy of the Ibuprofen-Loaded ZIF-8/Fe3O4 NPs Nanocarrier.

In this work, a one-pot multicomponent synthesis of the ibuprofen-loaded Fe3O4 nanoparticles-supported zeolitic imidazolate framework-8 (Ibu-ZIF-8/Fe3O4 NPs) nanohybrid was carried out. The ZIF-8/Fe3O4 NPs nanohybrid was used as a drug carrier for the in vitro release of ibuprofen in a PBS solution. The structure and morphology of the synthesized materials were investigated by powder X-ray diffraction (PXRD) analysis, transmission electron microscopy (TEM) analysis, UV-visible absorption studies, FTIR spectroscopy, and thermogravimetric analysis (TGA). The ibuprofen release kinetics was studied by UV-visible spectroscopy. The mechanism of drug delivery was thoroughly investigated and the Higuchi model was found as the best-fitted model for the ibuprofen release study. The 20 wt % Fe3O4 NPs-supported ZIF-8 nanohybrid exhibited more than 95% ibuprofen release efficiency in phosphate buffer saline of pH 7.4 within 2 h. The separation ability of the nanohybrid was very good, and it was easily separated by a simple commercial magnet. In order to investigate the cell viability, the cytotoxicity of ZIF-8, Fe3O4 NPs, and ZIF-8/20 wt % Fe3O4 NPs was investigated using MTT assays against Leishmania donovani promastigotes. The ZIF-8/20 wt % Fe3O4 NPs nanohybrid carrier exhibited a cell growth inhibition effect with a high correlation coefficient and low probability (p) values. The high release of drug molecules may be due to the more open site of the ZIF-8/Fe3O4 NPs nanohybrid. The drug release profile suggests that the nanohybrid can be potentially used as a drug carrier for targeted drug delivery systems.

An investigation of the structural and optical properties of modified barium magnesium fluoroborate glasses with hafnium oxide (HfO2)

AbstractGlasses of nominal composition xHfO2–(35-x)B2O3–15MgF2–35BaO, where x ranged from 0 to 0.2 mol% were fabricated using a melt-quenching technique. Structural characterization techniques, including X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and Raman spectroscopy, were employed to elucidate the glass network structure. The XRD patterns confirmed the amorphous nature of the studied glasses, while the FTIR and Raman spectra revealed that the incorporation of HfO2 may led to a transformation of trigonal BO3 units to tetrahedral BO4 units in the borate glass network. Deconvolution analysis of the FTIR and Raman bands provided quantitative insights into the extent of this structural rearrangement as a function of HfO2 content. UV–Vis absorption studies demonstrated that the optical bandgap of the glasses was widened with increasing HfO2 additions. This blue shift in the absorption edge was attributed to the increased formation of bridging oxygen bonds and reduced non-bridging oxygen content in the glass network. The results indicate that the studied glasses exhibit excellent compositional tunability through the incorporation of HfO2. The structural modifications and concomitant optical property enhancements suggest the potential of this glass system for various integrated photonic applications where low phonon energy and tailored transparency are highly desirable. The present work introduces a comprehensive investigation of the structural and optical property modifications in barium magnesium fluoroborate glasses induced by the addition of hafnium oxide (HfO2).

SYNTHESIS, SPECTRAL STUDIES AND EVALUATION OF DNA BINDING, PHOTOCLEAVAGE, ANTICANCER ACTIVITY OF RU(II) POLYPYRIDYL COMPLEXES OF 2-(3,4,5-TRIMETHOXY-PHENYL)-H-IMIDAZOLE[4,5-F][1,10]PHENANTHROLINE

The two novel Ru(II) polypyridyl complexes of the type [Ru(NN)2L](ClO4)2.2H2O,where NN is dmp=4,4-dimethyl-1,10 ortho phenanthroline and dmb=4,4-dimethyl 2,2-bipyridine and L is Intercalator ligand, TMIP=2-(3,4,5-Trimethoxy-phenyl)-H-imidazole[4,5-f][1,10]phenanthroline were synthesized and characterized by different spectroscopic techniques. The binding ability of Ru (II) complexes with CT-DNA was investigated by Biophysical studies – UV-Visible absorption studies, Fluorescence studies (Emission & Quenching) and Viscosity studies. The binding constants of these complexes from absorption studies are 1.2x105 M-1and 8x104M-1respectively.These values are less as compared to the existing TMIP complex [Ru(phen)2TMPIP]+2, indicative of the effect of substitution over the ancillary ligand which reduce the binding capacity of metal complex to CT-DNA. The results from the viscosity studies suggest an intercalative binding mechanism. The DNA cleavage studies show that the Ru (II) complexes successfully cleaved the pBR322 DNA. Both the complexes exhibit not notable anti cancer acivity.

Biosynthesis of ZnO nanoparticles using the young fruit of Borassus flabellifer: Characterization and photocatalytic removal of biohazardous safranin-O dye using solar irradiation

Here, ZnO nanostructures were synthesized for the first time from the young fruit of the Borassus flabellifer. X-ray diffraction study revealed that the unit cell of ZnO was hexagonal with particle size 39.83 nm. The field-emission scanning electron microscope (FESEM) images showed that spherical nanoparticles were formed. A sharp absorption peak was seen at 375 nm in the UV-vis absorption study, and the calculated excitonic band gap was 3.37 eV. The biosynthesized ZnO was used as a photocatalyst to remove the biohazardous safranin-O (SO) dye using solar irradiation. Freundlich isotherm model was used to study the adsorption behavior of SO onto ZnO. At optimum conditions, nearly 96.89% of the dye was degraded in just 80 minutes. Furthermore, the impact of catalyst dose, initial dye concentration, solution pH, and temperature on photodegradation was also investigated.

Facile fabrication of Au nanoparticles loaded Ce doped ZnO nanorods for efficient catalytic and photocatalytic decomposition of toxic pollutants in water

Plasmonic Au nanoparticles (NPs) have been deposited onto Ce doped ZnO nanorods prepared through wet chemical route to enhance their photodecomposition performance. The catalytic and photocatalytic performances were evaluated using a series of model pollutants such as 4-nitrophenol, antibiotic levofloxacin, cationic and anionic dyes under sunlight illumination. Various characterization tools such as XRD, Raman, FESEM, TEM, SAED, EDX, XPS, PL and UV–vis spectroscopy were used to examine the structure and physico-chemical properties of the fabricated photocatalysts. XRD, TEM, SAED, EDX, XPS and Raman analyses confirmed the existence of Ce doped ZnO and Au nanostructures while UV–visible absorption studies revealed the presence of SPR of Au NPs in the visible region. The results illustrated that decoration of Au NPs on Ce doped ZnO nanorods makes them outstanding catalyst as well as photocatalyst compared to pure Ce doped ZnO nanorods. The plasmonic nanohybrids with higher Au concentration exhibited superior degradation capability towards reduction and detoxification of 4-NP, decomposition of antibiotic levofloxacin and synthetic dyes, respectively. In addition, detailed study of possible mechanisms behind 4-NP reduction and photodegradation process have been explored. Furthermore, the quenching experiments elucidating ·O2- radicals as the main active species in the degradation mechanism have also been discussed. Moreover, the prepared Ce doped ZnO-Au hybrid plasmonic nanorods maintained high stability and stunning photoactivity even after four cycles which highlights it as a promising material for wastewater treatment.

The one-pot synthesis of photoluminescent polycarbonate based on the pyrolysis of citrate

Photoluminescent composites that are air-stable and water-resistant are important for outdoor applications such as road marking paints, light-converting membranes, fluorescent paints, and security inks. Photoluminescent thermoplastics fulfill all conditions but their preparation methods which are vastly based on mixing pre-synthesized fluorescent dyes and plastic could lead to emission quenching due to dye aggregation or thermal degradation. Herein, we demonstrated a simple method to prepare photoluminescent polycarbonate by thermal extrusion polycarbonate with citric acid and urea. UV-vis absorption and photoluminescent studies indicate that fluorescent carbon materials were formed via pyrolysis of the citrate. The composites exhibit light blue emission and a broad excitation band. The results demonstrated herein offer a cost-effective method to prepare diverse photoluminescent composites for outdoor applications.

Synthesis of donor-acceptor type 2D porphyrin based cyclic imides as an efficient photo catalysts in DSSC solar cell

Porphyrinated dimides-based materials differing in the nature of dianhydries namely TPP-2(FDI)-TPP and TPP-2(PMDI)-TPP has been synthesized and thoroughly characterized through various techniques including elemental analysis, FT-IR, UV–vis, 1H NMR spectra, fluorescence studies, and cyclic voltammetry. Furthermore, computational studies were also performed to investigate the electron transfer phenomena in TPP-2(FDI)-TPP and TPP-2(PM DI)-TPP. The 79.1% fluorescence intensity was reduced for TPP-2(FDI)-TPP and 95.8% was reduced for TPP-2(PMDI)-TPP as compared to cis-DATPP indicating the covalent interaction between the porphyrin moiety and dianhydrides, also indicating the transfer of an electron from cis-DATPP to dianhydrides. The HOMO, and LUMO level values for TPP-2(FDI)-TPP and TPP-2(PMDI)-TPP obtained from cyclic voltammetric analysis are −6.665 eV, −6.765 eV and −4.805 eV, −4.915 eV respectively. The HOMO and LUMO level values calculated through computational analysis are −4.939, −5.038, and −2.591, −3.366 respectively for TPP-2(FDI)-TPP and TPP-2(PMDI)-TPP. These results are found to be comparable with the UV–vis absorption studies indicating the synchronization of the calculated and experimental results. From the MEP analysis, we have found that the porphyrin acts as the nucleophilic center, whereas the polyimide moiety acts as the electrophilic center, indicating the easiest/possible transfer of electrons from porphyrin to 6FDA and PMDA. The intensity effect produced for TPP-2(FDI)-TPP and TPP-2(PMDI)-TPP showed a sublinear behavior and class 2 state. For TPP-2(FDI)-TPP the calculated Jsc was 4.09 mAcm−2 and Voc was 1.39V and for TPP-2(PMDI)-TPP, the value of Jsc and Voc were found 4.5 mAcm−2 and 1.77V respectively. The observed enhanced efficiency of 0.22% was calculated for TPP-2(FDI)-TPP which was due to the larger band gap and high LUMO level value.

Barium oxide nanorods: Catalyst concentration and surface defects' role in degrading methylene blue organic pollutant

In this study, BaO nanorods (NRs) were synthesized with inherent surface defects using the chemical coprecipitation process. The rich oxygen defect BaO NRs exhibited enhanced light sensitivity and effectively interacted with the organic pollutant methylene blue (MB) dye under UV-light illumination for wastewater treatment. The X-ray diffraction (XRD) analysis confirmed the highly crystalline tetragonal structure of the BaO NRs. Microstructural characteristics were examined using theoretical approaches such as Debye-Scherrer (DS), Williamson-Hall (W-H), and Size-Strain Plot (SSP), revealing an average crystallite size of approximately 30 nm. Field emission scanning electron microscopy (FE-SEM) revealed the rod-shaped structure of the BaO nanorods, with particles aligned on top of each other. UV–visible absorption studies demonstrated an increased optical bandgap in the BaO NRs compared to the bulk material. Photoluminescence spectroscopy revealed the presence of oxygen traps and surface defects, which aided the photodegradation process. The photocatalytic activity of the BaO NRs was assessed by degrading MB dye. We found that a concentration of 150 mg of BaO NRs exhibited the highest degradation efficiency at 85 %.