Crystallite Size Research Articles

A study on the facile synthesis of Cu-influenced organic framework and their characteristic properties

Today's nanomaterial scientific phases have been evolving through the most considerable novel MOF nano-characters. This study has described that the Cu (Copper) Nano-Metals based Metal-Organic Framework was synthesized by an affordable solvothermal method. With the facilitates of characterization methods, their factual physiochemical properties including Cu-MOF's crystalline characters, vibrational, surface morphology, surface chemical states, and obtained surface area have been examined. The X-ray diffraction–structural examination described the evident formation of metal oxide-coordinated MOF crystalline material. Before calcination, the MOF nanomaterial possessed an actual crystalline character of Cu-MOF with 22.3 nm of crystallite size then it became recrystallized after calcination. The co-contributions of Oxygen-linked organic molecular vibrational signatures upon Cu-O were analyzed through the Fourier Transform Infra-Red spectroscopy. Surface morphological magnifications exhibit plenty of pentagonal-shaped Cu-MOF nanomaterial with uniform distribution. Such a case also exhibits a flower-shaped Cu-MOF between pentagonal shapes with considerable surface porosity. X-ray photoelectron spectroscopy (XPS) has exhibited that the presence of oxygenated molecules contained copper oxide B.E states of synthesized Cu-MOF material. The UV–visible spectroscopy analysis has taken and the estimated bandgap of the Cu-MOF material is 2.3 eV. The thermal stability of the material has been analyzed through Thermo-Gravimetric analysis. To determine the internal structure of the Cu-MOF, an HR-TEM investigation was carried out. BET analysis exhibited 65.152 m2/g of active surface area. Due to the novel particle morphology with beneficial surface characteristics, the Cu-MOF possessed an efficient charge storage capacity of 383.3 Fg-1 due to its novel property.

Aftermath of Ag embedding on structural, optical, and supercapacitor electrode attributes of USP-grown CuO thin films

Here, ultrasonic spray pyrolysis method (USP) was utilized to produce pure and silver doped copper oxide nanostructures on glass substrates. Thereafter, several characterization techniques were conducted on the grown samples to delve into their morphological, structural, electrochemical, and optical aspects. The mentioned analyses were carried out by performing x-ray photoelectron spectroscopy, scanning electron microscope, X-ray diffraction, electrochemical impedance spectroscopy, galvostatic charge-discharge, cyclic voltammetry, and UV–visible spectroscopy measurements. Thus, the impact of silver impurity doping on the relevant aspects of host material were recorded as well as the features of unspoiled copper oxide films. Accordingly, the samples, as indicated by X-ray diffraction results, possessed (002) preferential plane orientation of copper oxide material along with the crystallite sizes ranging from 52.52 nm to 75.02 nm due to the imperfections caused by the silver doping. The scanning electron microscope images exhibited that the silver doping did not form significant modifications in the host material morphology where nanowire-like structures observed. The presence of the suggested materials in the films was verified by the x-ray photoelectron spectroscopy. Also, the UV–visible spectroscopy measurements detected that optical absorbance edge and bandgap energy values red shifted as a result of the impurity doping. The electrochemical supercapacitors performances of the silver doped copper oxide nanostructured thin films were inspected by using the GCD, EIS, and CV. The silver doped copper oxide films demonstrated a specific capacitance value of 66 F/g at a current density of 1 A/g in 1 M KOH electrolyte. From Nyquist plot, Rs, Rcor, Rpo, Ccor and Cc were obtained as 2.327 × 103 Ω.cm2, 43.63 × 103 Ω.cm2, 4.580 × 103 Ω.cm2, 111.5 × 10-6 S*s^a. cm-2 and 101.1 × 10-6 S*s^a. cm-2, respectively. The results indicated that the electrochemically synthesized the silver doped copper oxide electrodes can be obtained and developed as an alternative electrode material for supercapacitors (SCs).

Enhancing π-SnS thin films and fabrication of p-SnS/n-Si heterostructures through flow rate control in ultrasonic spray pyrolysis for improved photovoltaic performance

This study presents findings related to the characterization of cubic SnS (π-SnS) thin films and p-SnS/n-Si heterojunction structures produced simultaneously using the ultrasonic spray pyrolysis technique. In this context, the impact of different spray solution flow rates on the morphological, structural, optical, and electrical characteristics of the films was examined. Morphological analyses revealed that higher flow rates resulted in films with denser and smoother surfaces, approximately 6 nm in roughness. Additionally, it was observed that both the thickness and the growth rate of the films could be adjusted through the modulation of the flow rate. Structural analyses determined that the crystallite size increased and micro-strain values decreased with increasing flow rates. Optical evaluations indicated a decline in the optical band gap of the thin films from about 1.8 eV to 1.7 eV as the flow rates increased. This trend was consistently observed in the data obtained using the Tauc method and the derivative of transmission with respect to wavelength versus photon energy graphs. Electrical analyses revealed that the resistivity values of the thin films increased from 5.24 × 105 Ωcm to 1.64 × 106 Ωcm with increasing flow rates. Furthermore, I-V analyses of the Au/p-SnS/n-Si/Ag heterojunction structures indicated significant variability in key electrical properties. The saturation currents displayed a broad range, suggesting varying efficiencies in charge carrier collection across different samples. Similarly, the change of ideality factors pointed to differences in charge transport mechanisms, while the shifts in barrier heights indicated changes in junction properties with different fabrication conditions. The results of this study offer valuable perspectives for future research.

Investigation of structural, elastic, thermal, magnetic, optical, and photocatalytic properties of nanosized Mg-Mn-Li ferrites

AbstractNanoferrites of (Mn1-xMgx)0.8Li0.1Fe2.1O4 (x: 0–1.0, step 0.2) were synthesized by the sol–gel autocombustion method. The structural properties of the samples were characterized by X-ray diffraction, particle size analysis, transmission electron microscopy, and Fourier transform infrared spectroscopy. The X-ray diffraction patterns for the samples establish the nanoscale (38–54 nm) pure-phase spinel cubic structure (Fd-$$\bar{3}$$ 3 ̅ m). Also, the particle size analysis results demonstrate the narrow distribution of their particle sizes, which range from 10 to 33 nm. The impact of Mg2+ ion concentration on the thermal, elastic, magnetic, and optical properties of these samples was studied. The saturation magnetization decreases from 56.9 to 31.1 emu/g, and the coercivity increases from 65.8 to 106.8G with the addition of Mg2+ ions, showing thin S-shaped hysteresis loops revealing the samples’ soft magnetic behavior. Thermal results indicate that these samples are interesting candidates for thermoelectric applications due to their noticeably lower thermal conductivity, which ranges from 0.3572 to 0.5881 W/mK. The optical band gap values determined by using ultraviolet-visible diffuse reflectance spectroscopy range from 5.11 to 5.25 eV, where quantum confinement for crystallite size triggers a larger band gap. As the concentration of Mg2+ ions increases, their ability to degrade methyl green dye under ultraviolet radiation for 100 min rises from 13.6 to 61.1% with the addition of H2O2, an indication of their photocatalytic activity. Moreover, the optimum ferrite sample, Mn0.4Mg0.4Li0.1Fe2.1O4, maintained its photocatalytic efficiency for at least six reaction cycles. Graphical Abstract

Exploring the effect of Hf (IV) doping in spinel ferrite CoHfxFe2-xO4 on magnetic properties, electrochemical impedance, and photocatalytic activity: In-depth structural study

In this study, CoHfxFe(2−x)O4 nanoparticles (x = 0.0, 0.04, 0.08, and 0.12) were synthesized using the co-precipitation method. X-ray diffraction (XRD) analysis confirmed a pure spinel phase for the x = 0.04 sample, validated by Rietveld refinement, with crystallite sizes between 39 and 59 nm. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) confirmed the formation of the spinel structure and the proper valence states of the elements. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) verified the morphology and homogeneity of the samples. Magnetic property analysis revealed reduced saturation magnetization with increased Hf content. Impedance spectroscopy showed enhanced electrical resistivity with Hf incorporation. Photocatalytic tests demonstrated that doping improves the degradation efficiency of Orange G dye under UV-Vis irradiation, achieving yields between 9 % and 35 % after 60 min.

Alkaline electrochemical oxygen reduction boosted by trimetallic palladium–copper–gold nanoparticles

A Pd-Cu-Au/C nanocatalyst with a low content of Cu (8.2 at %) and Au (4.4 at %), and an average crystallite size of about 2 nm was synthesized by employing a one-pot two-steps borohydride reduction method in the presence of sodium citrate, characterized by energy-dispersive X-ray spectroscopy, X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy and examined for the oxygen reduction reaction (ORR) in an alkaline solution. Pd/C and Pd-Cu/C catalyst with 17 at % Cu, which were synthesized by the same method, and a commercial Pt/C were used for comparison. In addition, Pd-Cu-Au/C and Pd-Cu/C nanocatalysts were treated in acid with a purpose of their dealloying. The electrochemically active surface area of Pd was determined from COads desorption. It was found that the ORR on all catalysts follows first order kinetics with respect to O2 with four electrons transferred per O2 molecule. The catalysts were subjected to a short-term cycling stability test. Pd-Cu/C and Pd-Cu-Au/C were more active for ORR than Pd/C and Pt/C. The acid-treated catalysts exhibited higher activity compared to their untreated counterparts; both initially and after the stability test (up to 1.7 times in specific activity and 2 times in mass activity). The catalyst with the highest specific and mass activity after the stability test was the acid-treated Pd-Cu-Au/C which surpassed Pd/C by a factor of up to 2.5 in specific activity and 5.7 in mass activity. It was concluded that the acid treatment leads to a major dissolution of Cu from the nanoparticles, thus leaving a highly disordered Pd structure exhibiting increased activity for the ORR, while Au stabilizes Pd structure contributing to better performance after the stability test.

Novel Magnetite (Fe3O4)-Methylcellulose Nanocomposites Synthesized Using the Reverse Co-Precipitation Approach

A simple approach was used to create Fe3O4-methylcellulose (MC) nanocomposites, which were then analyzed using XRD, FTIR, and FE-SEM to determine their structure. The effective factors for enhancing the ratio of magnetite NPs in the samples were investigated using RTFM and optical absorbance. Fe3O4 was synthesized utilizing the reverse co-precipitation technique and magnetic characteristics. Fe3O4/MC nanocomposites with magnetite/MC weight ratios of 0, 0.07, 0.15, and 0.25 have been developed. The diffraction pattern of magnetite is well indexed in accordance with the spinal reference pattern of Fe3O4 (space group: R¯3m), as confirmed by the Rietveld analysis of XRD data of magnetite NPs with an average crystallite size of 50 nm. Magnetite’s insertion into the MC network causes a red shift in the band gap energy (Eg) as the weight percentage of magnetite nanoparticles in the samples rises. The MC, MC-7, MC-15, and MC-25 samples have Eg values of 5.51, 5.05, 2.84, and 2.20 eV, respectively.

One-Pot Phyto-Mediated Synthesis of Fe2O3/Fe3O4 Binary Mixed Nanocomposite Efficiently Applied in Wastewater Remediation by Photo-Fenton Reaction

A binary Fe2O3/Fe3O4 mixed nanocomposite was prepared by phyto-mediated avenue to be suited in the photo-Fenton photodegradation of methylene blue (MB) in the presence of H2O2. XRD and SEM analyses illustrated that Fe2O3 nanoparticles of average crystallite size 8.43 nm were successfully mixed with plate-like aggregates of Fe3O4 with a 15.1 nm average crystallite size. Moreover, SEM images showed a porous morphology for the binary Fe2O3/Fe3O4 mixed nanocomposite that is favorable for a photocatalyst. EDX and elemental mapping showed intense iron and oxygen peaks, confirming composite purity and symmetrical distribution. FTIR analysis displayed the distinct Fe-O assignments. Moreover, the isotherm of the developed nanocomposite showed slit-shaped pores in loose particulates within plate-like aggregates and a mesoporous pore-size distribution. Thermal gravimetric analysis (TGA) indicated the high thermal stability of the prepared Fe2O3/Fe3O4 binary nanocomposite. The optical properties illustrated a narrowing in the band gab (Eg = 2.92 eV) that enabled considerable absorption in the visible region of solar light. Suiting the developed binary Fe2O3/Fe3O4 nanocomposite in the photo-Fenton reaction along with H2O2 supplied higher productivity of active oxidizing species and accordingly a higher degradation efficacy of MB. The solar-driven photodegradation reactions were conducted and the estimated rate constants were 0.002, 0.0047, and 0.0143 min−1 when using the Fe2O3/Fe3O4 nanocomposite, pure H2O2, and the Fe2O3/Fe3O4/H2O2 hybrid catalyst, respectively. Therefore, suiting the developed binary Fe2O3/Fe3O4 nanocomposite and H2O2 in photo-Fenton reaction supplied higher productivity of active oxidizing species and accordingly a higher degradation efficacy of MB. After being subjected to four photo-Fenton degradation cycles, the Fe2O3/Fe3O4 nanocomposite catalyst still functioned admirably. Further evaluation of Fe2O3/Fe3O4 nanocomposite in photocatalytic remediation of contaminated water using a mixture of MB and pyronine Y (PY) dyestuffs revealed substantial dye photodegradation efficiencies.

Role of Fe supplantation in tailoring structural, electrical conductivity, and magnetic properties in La2Ni1-xFexMnO6 double perovskites

Double perovskite system La2Ni1-xFexMnO6 (x = 0, 0.2, 0.5, 0.8 & 1.0) were developed using sol-gel method. Rietveld refinement revealed monoclinic structure (ordered) along with occurrence of rhombohedral and orthorhombic structures suggesting antisite cationic disorder. Crystallite size and average grain size of samples varied between 454 and 1058 Å and 0.774–1.429 μm respectively. XPS revealed the dual oxidation states of Ni, Fe, and Mn ions. La2NiMnO6 attained the highest DC conductivity among all compositions. The increase in DC conductivity with temperature suggested the semiconducting behavior of the samples, that explained by Thermal Activation (TA) and Variable Range Hopping (VRH) conduction mechanisms. Obtained activation energy(Edc) showed increasing trend with temperature. M-H loops exhibit a ferromagnetic nature accompanied by antiferromagnetic interactions as suggested by exchange bias and partially saturated loops. La2NiMnO6 attained the highest saturation magnetization (29.81emu/g) and decreased with Fe supplantation. The possible mechanism of tuning conductivity and magnetic properties of La2Ni1-xFexMnO6 has been discussed in detail.

Green synthesis, characterization, and photocatalytic activity of superparamagnetic MgFe2O4@ZnAl2O4 nanocomposites

MgFe2O4@ZnAl2O4 magnetic nanocomposites were synthesized with the easy and green sol–gel method, and their photocatalytic efficiency was followed toward degradation of reactive blue 222 (RB222) dye under visible light irradiation. Prepared nanocomposites were fully characterized. The SEM and TEM images revealed the spherical morphology of the produced nanocomposites, with average size of 20–25 nm. The XRD pattern of sample exhibited the successful synthesis of the MgFe2O4@ZnAl2O4 MNCs with crystallite size 13 nm. The saturation magnetization (Ms) of the nanocomposites was examined using VSM, indicating a value of 6.59 emu/g. The absence of Hc and Mr values confirms the superparamagnetic nature of the nanoparticles. In addition, the surface area was calculated to be 78.109 m2/g utilizing BET analysis, and the band gap was determined to be 1.88 eV by DRS analysis. The photocatalytic, photolysis, and adsorption performance were investigated and result shown photodegradation activity was higher than others. These results confirm the synergetic effect between the MgFe2O4@ZnAl2O4 MNCs and visible light irradiation to degradation of organic dye. The results indicate that rapid degradation of 96% of RB222 dye occurred in just 10 min, with a TOC removal rate of approximately 59%. Furthermore, radical scavenger agents also clarified photodegradation of RB222 dye.

Exploring the role of deep eutectic solvents in enhancing the properties of PMMA for potential electrolyte films

In this study, a novel series of solid PMMA containing deep eutectic solvent (DES) (PMMADES) (Mw = ∼28,374 g mol−1) was successfully synthesized via free radical polymerization of methyl methacrylate (MMA) in different types of DES (e.g., choline chloride (ChCl): 1,2-butanediol (1,2-BD)-DESI, ChCl: 1,3-butanediol (1,3-BD)-DESII, and ChCl: 1,4-butanediol (1,4-BD)-DESIII) in order to overcome the brittleness of commercial PMMA film. Interestingly, flexible PMMADES films with a reduced glass transition temperature (Tg) from 73.36 °C (PMMA) to 55.38 °C were obtained. This is due to the ability of DES to act as a plasticizer by forming interactions with PMMA, as confirmed by FTIR analysis. In addition, the incorporated DES also results in a reduction in the number of crystalline grains, as observed from their optical micrographs. This is due to the increment in amorphous content, as proven by XRD analysis, which shows a reduction in crystallite size from 1.20 nm (PMMA) to 1.12 nm upon the addition of DES. Also, this study found that the PMMADESI system, which involved the incorporation of ChCl: 1,2-BD (DESI), exhibited the highest ionic conductivity (∼10−8 S cm−1) and lowest value of Tg (55.38 °C). This was due to the closest position of the hydroxyl group in 1,2-BD, which contributes to the greater disorderliness and wider ion distribution of the PMMA matrix.

Energizing tomorrow with the dithiocarbamate complexes: Unveiling BaS3:La2S3:PrS1.7 tri-metallic chalcogenide semiconductor decorated electrode for supercapacitors and electro-catalysis

This study investigates the energy efficient and novel BaS3:La2S3:PrS1.7 nanocomposite chalcogenide system synthesized using a single source precursor technique. The prepared metallic sulphide was marked by narrow band gap of 3.6 eV and 17.39 nm average crystallite size. Functional group analysis indicated the presence of various bonds inclusive of the metal sulphide bond. Morphologically, these nano-composite chalcogenide was expressive of the irregular shaped particles arranged in the form of agglomerates. The decomposition pattern of this chalcogenide took place in two steps shown by the thermal gravimetric analysis recorded in the range of 0–800 °C. The electrochemical charge-storing behavior was evaluated. According to cyclic voltammetric results in 1 M KOH, the fabricated electrode demonstrated favorable charge storage capabilities with a specific capacitance of 776.36 F g−1. This implies that the electrode has a large amount of potential for storing energy. Additionally, the impedance studies showed that this electrode had a specific power density of 7417.69 W kg−1 and a Rs = 1.03 Ω. The OER overpotential and Tafel slope values are 457 mV and 78 mV/dec, respectively, while electrode produced a Tafel slope of 200 mV/dec and a HER overpotential value of 233 mV.

Designing and synthesis of perovskite nanocrystals: a promising wide-spectrum solar light-responsive photocatalyst and lead ion sensor.

Perovskites are an emerging material with a variety of applications, ranging from their solar light conversion capability to their sensing efficiency. In current study, perovskite nanocrystals (PNCs) were designed using theoretical density functional theory (DFT) analysis. Moreover, the theoretically designed PNCs were fabricated and confirmed by various characterization techniques. The calculated optical bandgap from UV-Vis and fluorescence spectra were 2.15 and 2.05eV, respectively. The average crystallite size of PNCs calculated from Scherrer equation was 15.18nm, and point of zero charge (PZC) was obtained at pH 8. The maximum eosin B (EB) removal efficiency by PNCs was 99.56% at optimized conditions following first-order kinetics with 0.98 R2 value. The goodness of the response surface methodology (RSM) model was confirmed from analysis of variance (ANOVA), with the experimental F value (named after Ronald Fisher) of 194.66 being greater than the critical F value F0.05, 14, 14 = 2.48 and a lack of fit value of 0.0587. The Stern-Volmer equation with a larger Ksv value of for Pb2+ suggests its greater sensitivity for Pb2+ among the different metals tested.

Unveiling the potential of NiO–ZnCo2O4 nano-composites: Electrical, optical, electrochemical and antibacterial investigation

Zinc Cobaltite (ZCO) and Nickel Oxide (NiO) nanoparticles (NPs) were synthesized using a sol-gel technique, and their composites with different weight ratios were prepared using a straightforward sonication method. The NiO and ZCO NPs had small crystallite size of 10 nm and 18 nm, respectively. According to the ultraviolet–visible (UV–Vis) spectra, pure NiO and ZCO NPs exhibited band gaps of ∼3.5 eV and 3.3 eV. Antibacterial activity against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacterial strains was also tested for the composite counterpart and its equivalents. Compared to pure NPs, the composite of 30 % ZCO-NiO (NZ3) had higher antibacterial activity with zone of inhibition of ∼13 mm against E. coli. The electrical and electrochemical properties were also explored and it was found that the composite of 50 % ZCO-NiO (NZ5) shows high specific capacitance of 188 F/g.

Structural, linear/nonlinear optical characteristics and radiation shielding effectiveness of Cu4O3/Cu2O dual-phase thin films: Influence of oxygen flow rate in reactive sputtering process

In the present work, we investigated the impact of oxygen flow rate on the structural, linear, and nonlinear optical characteristics while also evaluating the radiation shielding effectiveness during reactive radio frequency (rf) sputtering in the deposition of Cu4O3/Cu2O dual-phase thin films. Microstructural analysis revealed distinct changes with increased OFRs, switching from a Cu2O cubic structure phase to a Cu4O3 tetragonal structure phase. The XRD patterns revealed good crystallinity, and the crystallite size of the film reduced from 28 nm to 22 nm, and the microstrain exhibited an opposing trend as the oxygen flow rate increased. In contrast, investigating the optical properties of dual-phase Cu4O3 and Cu2O thin films using UV–Vis–NIR spectroscopy revealed intriguing trends in the absorbance spectra, absorption coefficient, and extension index. The apparent bandgap increases from 2.0 eV to 2.62 eV with increasing oxygen flow rates. In addition, nonlinear optical parameters, including the nonlinear refractive index n2 linear, nonlinear sensitivity (χ1 and χ3), and nonlinear absorption coefficient βc were calculated to demonstrate the applicability of these materials. The dual-phase structure of the films enhances their potential for effective radiation shielding. Our findings provide valuable insights into the design of properties of Cu4O3/Cu2O dual-phase thin films for applications ranging from photoelectric and nonlinear optical devices to radiation shielding effectiveness.

Green Synthesis of Silver Nanoparticles With Cyclosorus dentatus and Nephrolepis biserrata and Their Antioxidant, Anti‐Inflammatory Studies

ABSTRACTThis study examined the synthesis of silver nanoparticles (SNPs) with aqueous extracts of Cyclosorus dentatus and Nephrolepis biserrata fronds and the evaluation of their biological activities. Mixing of AgNO3 solution and the aqueous extracts resulted in color change, indicating the formation of SNPs. UV‐Vis spectroscopy analysis gave a surface plasmon resonance (SPR) peak at approximately 420 nm, confirming the presence of the synthesized SNPs. Infrared analysis showed C‐O, N‐O, and C‐C vibrations or stretching and aliphatic vibrations of hydrocarbon chains of the synthesized SNPs. x‐Ray diffraction (XRD) analysis indicated the SNPs were face‐centered, cubic, and crystalline in nature, with crystallite sizes. The scanning electron microscopy (SEM) shows the aggregation of the spherical shape nanoparticles. The SNPs significantly reduced phosphomolybdenum and captured H2O2 with respective IC50 values of 61.55 and 29.03 µg/mL for C. dentatus SNP (SNP‐Cd), and 92.61 and 9.07 µg/mL for N. biserrata SNP (SNP‐Nb), respectively. In terms of albumin‐denaturing activity, the SNPs gave an IC50 value of 21.20 µg/mL for SNP‐Cd and 7.18 µg/mL for SNP‐Nb. Thus, this work confirmed that SNP‐Cd and SNP‐Nb are potential therapeutic agents for treating oxidative stress, inflammatory problems, and related diseases.

Phytogenic aqueous extract mediated fabrication of Ag-Fe2O3 nanohybrids for detoxification of carcinogenic Congo Red dye: An Environmental Remediation approach

<p>In current study environment benign silver-iron oxide (Ag-Fe2O3) nanohybrid structures are fabricated as catalyst for CR dye decolorization. Industrial wastewater stream possesses several toxic dyes which are toxic carcinogen pollutants cause severe environmental disorders. Detoxification of Congo Red dye is carried out by silver-iron oxide nanohybrid structures having latent catalytic efficiency for dye decolorization. Silver iron oxide nanohybrid materials are fabricated from AgNO3, FeSO4/ FeCl3 and Citrus limon aqueous extract by doping AgNPs on Fe2O3 materials. For characterization of Ag-Fe2O3 nanostructures, UV-Visible, X-ray diffraction (XRD), Scanning electron microscope (SEM) and Fourier transform infrared (FT-IR) techniques are used. The crystallite size is measured from Debye Scherer equation and average size calculated is 54.3 nm. Furthermore, UV-Visible spectrophotometer is used to study the catalytic efficiency of Ag-Fe2O3 nanohybrid material which is observed to be >80% within 10 minutes. Moreover, parameters like contact time, dosage of catalyst, temperature and pH are measured to optimize reaction conditions for the dye degradation by adding prepared nanohybrids. The kinetic studies were performed for the degradation reaction and were originate to follow first order kinetics. Reusability test is also applied to check the stability of nanohybrid catalyst that affirmed it to be as highly stable nanomaterial.</p>

Influence of 60Co gamma radiation on the structural, morphological and optical properties of hydrothermally synthesized MoO3-CeO2 nanocomposite.

The influence of 60Co gamma radiation on Molybdenum Oxide-Cerium Oxide (MoO3-CeO2) nanocomposite is investigated in the present study. The MoO3-CeO2 nanocomposite was synthesized by conventional hydrothermal route. Ammonium hepta molybdate tetrahydrate [(NH4)6Mo7O24.4H2O] and cerium nitrate [Ce (NO3)3.4H2O] were used as the precursors. The composite was subjected to high energy gamma irradiation for different doses of 50, 100 and 150 kGy using 60Co gamma irradiation chamber. The structural study was carried out using X-ray diffraction, the morphological studies were carried out using scanning electron microscopy and ultraviolet-visible spectroscopy was carried out to study the optical properties before and after irradiation. The crystallite size was found to increase with increasing doses of gamma irradiation. The morphology of the samples shows that the nanoparticles tend to agglomerate with increasing doses of gamma radiation. The energy bandgap of the MoO3-CeO2 nanocomposite was calculated before and after irradiation and found to decrease with increasing doses of irradiation upto 100 kGy and then increases for 150 kGy.

Rietveld refined structural, optical and temperature dependent impedance spectroscopy of NiO–ZnO heterostructure composite: Synthesized through solid state method for high-frequency devices

Multifunctional NiO–ZnO heterostructure composite powder is economically synthesized through a solid-state route having a crystallite size of 23 (±2) nm. Chemical composition is identified through FTIR, the peak associated with Zn–O is detected at 1049 cm−1. However, the peaks detected at 870 cm−1 and 590 cm−1 show Ni–O stretching vibrations. UV-DRS technique is employed to estimate the energy band gap (Eg) around 3.18 eV. The impedance studies confirmed the presence of a non-Debye-type relaxation mechanism, electrical parameters confirm the contribution of electroactive regions i.e. grains and interfaces. An equivalent circuit model (R-CPE) is employed to measure various electrical parameters. Adiabatic small polaron hopping model is applied to estimate activation energies for Ni+2 (0.30 eV), Zn+2 (0.35 eV), and bulk (0.32 eV) respectively. The hopping length at the interface is estimated at around 0.8 Å by employing Mott's variable range hopping model. Jonscher's power law (JPL) is used to fit ac conductivity data, and conclude activation energy around 0.3 eV. The conduction mechanism through the whole frequency range (1–107 Hz) is governed by correlated barrier hopping. Various physical parameters i.e. binding energy (Wm), hopping length, and barrier height compared throughout the whole temperature range (313–393 K). The rate of increase in real permittivity at low frequency is related to the disorder of the cation at sublattices. These results deduced potential for NiO–ZnO heterostructure composite for high dielectric permittivity with low tangent loss for high energy storage applications.

Latent fingerprint imaging using irradiated novel mixed metal oxides (MXOY, M=Ba, Zn, Al, Ce) nanophosphor.

Latent fingerprint developed at the site of crime is considered as crucial physical evidence in forensic investigation. The mixed metal oxides (MXOY, M=Ba, Zn, Al, Ce) nanophosphor was synthesised by irradiating the precursor solution with 60Co gamma radiation followed by solution combustion method. The structural, morphological, optical characteristics and fingerprint imaging were studied using X-ray diffraction (XRD), scanning electron microscopy, UV-visible spectroscopy and powder dusting method, respectively. The XRD results revealed that the average crystallite size is found to be 30nm with the estimated bandgap of 3.18eV. The broadband UV exited luminescence of the phosphors was observed at λMax=330nm. The PL spectrum shows three emission bands at 432, 444 and 460nm that corresponds to blue regions, suggesting that the synthesised nanophosphor is a potential luminous material for latent fingerprinting and luminescent devices.