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In this work, we have successfully synthesized pure and Cobalt (2.5% and 5%) doped-MnO2 nanorods via a simple hydrothermal route. The morphological, structural, optical, and antibacterial effects, were studied using advanced analytical techniques. The grain sizes of as-prepared nanorods, were calculated in the range of 21–26 nm. The UV–Visible abso...
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Results of studies on pure and Nd doped SnO 2 Nanorods wereprepared by sol gel method,the structural and optical properties were investigated. With the aim of understanding the structural and optical properties, a systematic investigation as a function of annealing temperature has been carried out. The XRD, TEM studies shows the samples have a tetr...
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... However, the displacement in absorption band gap edge is associated with the formation of optical band gap. Moreover, their correlation can be examined through the Tauc's plot [36,37] which leads to relation between absorption coefficient (α) with the energy of the input photon [38]. ...
In this study, low temperature electrical conductivity of pristine polyaniline and polyaniline/activated charcoal nanocomposites with four different loading concentrations of activated charcoal (2, 4, 6, and 8 wt%) synthesized through chemical oxidative polymerization method is presented. Surface analysis of the prepared nanocomposites was done using Field emission scanning electron microscope. The energy band for pristine are found to be 2.68 eV whereas it is decreases up to 2.41 eV after introducing 8 wt% loading concentration of AC. The Pristine PANI sample contains the high value of electrical conductivity i.e. 32.34 S/cm which increases upto 168.87 S/cm with the 8 wt% loading of activated charcoal in PANI matrix which is also evident with the increase in AQ/AB ratio from 0.214 to 0.408 using FTIR. The Mott’s VRH model was found to be in agreement to explain the conduction mechanism in these samples. The Debye temperature for one-dimensional to two-dimensional hopping are found to be ~ 15, 18, 19, 22, 25 K whereas Debye temperature for two-dimensional to three-dimensional hopping are found to be ~ 28, 34, 36, 44, 46 for S0, S1, S2, S3, S4 samples, respectively. The enhancement in density of states from 3.05 × 10¹⁹ to 30.99 × 10¹⁹ eV⁻¹ cm⁻³ and decrease in hopping distance from 341.59 to 191.38 nm in high tempreature region with the increase of loading concentrations of activated charcoal indicates the requirement of lesser hopping energy for charge transport.
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... When compared to the Li ion system, the electrochemical demonstration showed that the electrolytes oxidation stability can be achieved with an electrode which naturally slows down magnesium ion diffusion and reversible cycle, where as it supplies two electrons per redox playing a significant role in raising energy densities of Mg batteries as compared to Li-Batteries [17][18][19]. To interact well with a variety of metal oxides, such as CuO [20,21], MnO 2 [22,23], RuO 2 [24], NiO [25,26], Co 3 O 4 [27], and ZnO, the material in consideration needed to have a broad range of stand of the structural and surface properties. Additionally, significant progress has been made in enhancing the material's overall performance. ...
Magnesium batteries provide a promising alternative to traditional energy storage solutions due to their impressive energy density, potential safety features, and cost-effectiveness, making them highly suitable for large-scale applications. The solid state synthesis of MgCoSiO4 is reported in this work. The produced magnesium cobalt silicate nanoparticles are treated with 450 V of DC glow discharge plasma for 15 min of exposure time. The novel aspect of the MgCoSiO4 material generated in a solid state is highlighted in this research work. This material underwent plasma treatment, which changed its surface and improved its performance. Through testing and investigation, these modifications resulted in increased conductivity and overall electrode material efficiency, demonstrating the substantial influence of the treatment material functionality. It enhances the electrochemical characteristics by altering the surface energies, adhesion, and wettability. Thus the as prepared sample was made as the electrode material for further investigation. The sample’s structural, morphological, and chemical makeup was examined using XRD, FTIR, FESEM and wettability. Owning to the exclusive sponge-like morphology and more porous air plasma treated MgCoSiO4 electrode displays higher specific capacitance of 1232 F/g than the pure 296 F/g which can also exhibit 89% of capacitance retention after 6000 cycles. These results suggests that the MgCoSiO4 electrode material treated with air plasma is appropriate for use in energy storage applications.
... Many researchers have sought to improve the optical properties of various nano-compounds. Nadim Ullah et al. [5] successfully synthesized pure cobalt and cobalt doped MnO 2 nanorods using a simple hydrothermal method. The UV-visible absorption spectroscopy indicates a wide absorption band, centred at ~ 450 nm for pure and ~ 465 nm for cobalt-doped MnO 2 nanorods. ...
The present work scrutinizes a few uses of barium titanate BaTi1–xZrxO3 (0.0 ≤ x ≤ 0.3) nanoparticles, which are an innovative and highly promising material for a variety of applications, including optical applications; and waste water treatment. To estimate the quality of a synthesized powder relative to an already existing commercial powder, the samples were prepared using cheaper raw materials and simpler, faster procedures than those reported in other literature at lower annealing durations and temperatures. The prepared samples were characterized by field emission scanning electron microscopy (FESEM), and Raman spectroscopy, which confirmed the coarse nature of the samples and the system's tetragonality. Furthermore, UV–visible absorbance of all compositions was studied. It has been determined that optical transition is directly allowed after extensive research, and the optical band gap (Eg) values increase with increasing (Zr⁴⁺) ion concentration. The derivation of absorption spectrum fitting (DASF) technique was used to support the type of transition and calculate the value of the coefficient of electronic transition (n). Samples can perform overall water splitting and CO2 reduction processes. The Langmuir and Freundlich isotherms were used to comprehend the procedure of adsorption on the investigated samples. The BaTi0.8Zr0.2O3 has been used to successfully remove 99.9% of heavy metals (Cr⁶⁺) from wastewater. The obtained results provide new insights into the control of the structure, and optical behaviors in BaTi1–xZrxO3.
... In recent years, the relevance of transition-metal oxide nanoparticles (NPs) has drawn a lot of attention due to their wide range of applications [1]. Some notable applications include their role as medicinal agents, in optoelectronic devices [2,3], new-generation batteries, bactericidal agents [4,5], waste-water treatment and catalytic processes. These applications are governed by their physical and chemical properties, which depend on their atomic and electronic structures [6][7][8]. ...
This paper reports a novel green fabrication of copper ferrite (CuFe2O4) nanoparticles (NPs) from Cissus rotundifolia plant extract. The Fourier transforms infrared spectroscopy (FT-IR) spectrum exhibited intrinsic stretching at the tetrahedral position of Fe–O at 591 cm-1 and the octahedral stretching of Cu–O at 402 cm-1 respectively. The fine diffraction pattern in the X-ray diffraction spectrum showed the formation of well-crystalline NPs. The mean crystallite size was calculated to be 17.33 nm. The High-resolution Transmission Electron Microscopic (TEM) images of the NPs showed their roughly spherical shape and irregular morphology. The Zeta potential was calculated to be -29.7±0.3 mV, indicating a negative charge over the CuFe2O4 NPs. The formation of spinel ferrite was confirmed from the characterization data. The photocatalytic activity of CuFe2O4 NPs was examined against the methylene blue (MB) dye, showing 82% degradation of dye under UV-visible light. The reusability experiment showed that the catalytic activity was not much decreased till the 4th cycle. The antibacterial activity of the synthesized CuFe2O4 NPs was tested against Bacillus subtilis, Staphylococcus aureus, Bacilus pumilis, Escherichia coli, Pseudomonas aeruginosa, and Salmonella abony through the Agar well diffusion method. A zone of inhibition of 12±0.2, 11±0.4 against Bacillus subtilis and Bacillus pumilis and 14±0.4, 18±0.3, 12±0.2 was obtained and E. coli, P. aeruginosa and S. abony respectively at 75 mg/mL which showed appreciable antibacterial activity.
... The band gap values of the samples were determined from the Kubelka-Munk function and presented in Table 1 and Fig. 2b, from which it can be observed that the band gap energy (E g ) is increased from 2.74 to 2.91 eV after the exfoliation process [45][46][47]. As a result, the small blue shift can be ascribed to the quantum confinement effect (QCE) due to the reduction in the thickness and size of the layers of g-C 3 N 4 [25,26,38,48]. ...
The rational design and development of highly-active photocatalytic materials for the degradation of dangerous chemical compounds, such as parabens, is one of the main research pillars in the field of photocatalysis. Graphitic carbon nitride (g-C3N4) is a 2D non-metal material and is considered one of the most promising photocatalysts, because of its peculiar physicochemical properties. In this work, porous g-C3N4 nanosheets (CNNs) were successfully prepared via thermal exfoliation of bulk g-C3N4 (CNB). A thorough physicochemical characterization analysis before and after the exfoliation process was performed, revealing the improved textural characteristics (surface area of 212 m²/g), chemical stability, and optical properties (wide band gap of 2.91 eV) of CNNs compared to the CNB. Then, both CNB and CNNs were comparatively assessed as photocatalysts for the degradation of methyl-, ethyl- and propylparaben (MP, EP, and PP), as well as of their mixture. CNNs with high surface area display superior photocatalytic performance under solar irradiation, offering > 95% degradation efficiency to all parabens, in contrast to the much inferior performance of CNB (< 30%). Several experimental parameters, involving catalyst concentration, initial concentration of parabens, and irradiation type were thoroughly investigated for the degradation of MP over CNNs. Moreover, various scavengers were employed to discriminate the role of different reactive species, revealing that superoxide anion radicals (·O2–) play a pivotal role in the degradation process, in contrast to hydroxyl radicals (·OH). The present results pave the way towards the facile synthesis of high surface area CNNs with improved textural and electronic characteristics, which can be applied in various environmental applications.
... The well-known hydrothermal approach was used for synthesizes of pure and Nickle doped CoFe 2 O 4 nanostructured with varying concentrations (Ni x Co 1-x Fe 2 O 4 where x = 0%, 2%, 4% and 6%) [24]. O] were used as the raw materials sources of Fe, Co, and Ni, respectively. ...
... For the antibacterial activity of Ni X Co 1-x Fe 2 O 4 where x = 0, 0.98/2%, 0.96/4%, and 0.94/6% were tested by using the well-known Agar-well diffusion method [24]. Initially, the volume of pure culture of three different bacterial strains i.e., Staph-aureous, E.Coli, and Psedomenas aeroginosa was spread on whole agar-plates and then with help of Cork borer a 5 mm hole was made. ...
In the current study, Ni doped CoFe 2 O 4 nanoparticles were fabricated using well-known hydrothermal method. The structural, morphological, optical, and antibacterial activity were analyzed through the latest analytical techniques. The Fd-cubic spinel crystal structure was observed with variations in crystallite sizes and lattice parameters of synthesized samples. The growth of spherical and uniform nanoparticles with the presence of expected elements are observed from field emission scanning electron microscopy and energy dispersive x-rays analysis, respectively. A broad absorption band was shown in UV-visible absorption spectroscopy in the wavelength range of 200-320 nm. A significant increase in the energy band gap was observed from 2.98 eV to 3.56 eV as the concentration of dopant increased from 2% to 6%. The antibacterial activities of the samples were investigated against Staph aureus, Pseudomonas aeruginosa and E. Coli through the well-known Agar well diffusion method. The pure and Ni-doped CoFe 2 O 4 exhibits a maximum zone of inhibition (3-25 mm), proposing that these materials are efficient against bacterial resistance. Further, the enhancement in value of the inhibition zone by substitution of Ni at cobalt sites recommended that it is a potential candidate for biomedical applications and can be highly effective against the high resistance of different bacteria.
... The morphology of materials, encompassing their electrical, chemical, and physical attributes, plays a pivotal role in determining their properties [7]. As a result, extensive research efforts have been dedicated to investigating the phase, dimensionality, size, and shape of various materials. ...
The inconsistent conductivity and surface roughness of commercially available chemical vapour deposition (CVD) monolayer graphene films have limited their widespread adoption in optoelectronic devices. This study presents a novel approach to address this issue by investigating the effect of post-thermal annealing on the sheet resistance (Rs) and surface properties of CVD monolayer graphene films on quartz substrates. The films undergo thermal annealing at temperatures ranging from 200 to \(600\,^{\circ }\hbox {C}\) in a nitrogen environment using a one-zone tube furnace. Remarkably, annealing the graphene films at \(400\,^{\circ }\hbox {C}\) leads to a remarkable reduction in Rs by 58.1% and surface roughness (Ra) by 33.3%. In-depth analysis using Raman spectroscopy reveals that the Rs reduction is attributed to increased charge density from doping effects, while the Ra reduction is attributed to thermal-induced mechanical biaxial tensile strain. Moreover, the Raman spectrum exhibits a remarkable 67.3% reduction in the quality–intensity ratio (\({I}_\textrm{D}\)/\({I}_\textrm{G}\)) of the graphene film annealed at \(400\,^{\circ }\hbox {C}\), confirming a defect-free state, and further validating the healing effect on the commercially procured graphene films. These findings offer great potential for enhancing the performance and reliability of commercially available CVD monolayer graphene films in optoelectronic devices. By introducing a practical solution to improve conductivity and surface roughness, post-thermal annealing at an optimal temperature of \(400\,^{\circ }\hbox {C}\) presents a promising and innovative approach to unlock the full potential of CVD monolayer graphene films in various technological applications.
... The bandgap energy of AgNPs was calculated by using the Tauc equation (Khan et al., 2019;Ullah et al., 2021); ...
Antibiotic resistance among bacterial infections has become a leading problem in the medical industry. Herein, we have synthesized the silver nanoparticles (AgNPs) from fresh leaves of Moringa oleifera extract. The synthesis was optimized by varying the concentration of AgNO3, plant extract, and contact time. The as-prepared nanoparticles (NPs) were examined by various advanced analytical tools including UV–Vis, FTIR, XRD, SEM-EDS, TEM, DSC and TGA to confirm the morphology, particle distribution, and thermal effect. The antimicrobial potential of AgNPs was determined against selected pathogenic strains including Klebsiella pneumoniae (ATCC® 13883™), Escherichia coli (ATCC® 25922™), Acinetobacter baumannii (ATCC® 19606™), and Pseudomonas aeruginosa (ATCC® 27853™). The ager-well assay showed inhibitory zones in the range of 7–15 mm with MIC value of 250 μg/ml which suggests that strains are sensitive in growth inhibitory conditions. The present work affirms that AgNPs mediated through leaves of Moringa oleifera exhibits a higher antibacterial potential as compared with previous reported studies, and can be used in biomedical science for disinfection applications.
... The XRD spectral analysis of pure and Ag-doped ZnO are presented in figure 1 The high intensity of (101) peak suggest that growth of nanostructures has taken place essay direction of crystallization of ZnO [20]. The average grain size was estimated using the well-known Scherrer relation [21]. ...
Antibiotic resistance is concerned with public health and a serious threat in modern world. Pathogenic strains are rapidly developing resistance against antibiotics and limiting the treatment options. Nanostructured zinc oxide (ZnO) shows significant results when doped with silver (Ag), therefore used as an antibacterial agent. In this work, we synthesized pure and varying concentration of Ag-doped ZnO nanoplates through a one-step hydrothermal route. The structural, morphological, and optical properties of prepared nanostructures were comparatively studied. Furthermore, we have performed the ager-well assay, minimum inhibitory concentration study, and minimum bactericidal concentration study of synthesized nanoplates against five different bacterial strains including A. baumannii, P. aeruginosa, E. coli, K. pneumoniae, and S. aureus. The antimicrobial screening shows that Ag-doped ZnO nanoplates are more effective against all pathogenic strains as compared to pure ZnO, and therefore can be used in biomedical science.
