SEM Photographs Research Articles

THE EFFECTS OF SEPIOLITE LOADINGS ON MECHANICAL, THERMAL, AND MORPHOLOGICAL CHARACTERISTICS OF NATURAL RUBBER/EPOXIDISED NATURAL RUBBER (NR/ENR-25) BLENDS

Sepiolite has been used widely as nanofillers to improve the properties and compatibility of rubber blends, and due to its magnesium silicate hydrates contents, the sepiolite may also function as a thermal stabilizer. These works investigate the effects of sepiolite loadings on curing, mechanical, thermal, and morphological characteristics of natural rubber/epoxidized natural rubber (NR/ENR-25) blends. The blends were made using a two-roll mill technique using standard vulcanization reagents of sulfur and carbon black as the main filler, and their vulcanization characteristics were investigated using the rheometry technique. Furthermore, the thermal, mechanical, and morphological characteristics of the blends were evaluated using thermogravimetry, tensile tests, and electron microscopy, respectively. It was found that an increase in the sepiolite loadings decreased scorch times (ts2 and t90), whereas optimum sepiolite loading with higher tensile strength was 3 phr, which lowered down when the sepiolite loading was increased up to 9 phr. The thermogram of blend specimen with 3 phr sepiolite loading also exhibited superior thermal stability, that is, has higher degradation temperature at 5% weight loss. Fracture surface SEM photographs of the blend specimens showed finely distributed sepiolite particles at optimum sepiolite loading 3 phr and exhibited agglomerations when the loadings were increased up to 9 phr.

Hydrazidomethyl starch as a pH-sensitive coating for magnetic core in tailored magnetic nanoparticles with selective doxorubicin release

The work aimed to use and modify starch as a biodegradable and biocompatible polysaccharide to create a modern pH-sensitive anticancer drug carrier based on a hydrazone bond. The multi-step reaction created a material that can bind to the carbonyl group of anticancer drugs. Additionally, polysaccharide was used to coat magnetic nanoparticles to increase the applicability of the carrier system. At each synthesis stage, the material was characterized in detail by performing FTIR-ATR spectra, thermal analysis, XRD, and SEM photos. In the next step, doxorubicin was loaded with a maximum of 19 % drug loading to the carrier via hydrazone bond. In the last research stage, the carrier-hydrazone bond-drug system was tested in solutions with different pH values, imitating the environments of a cancer cell, a healthy cell, and their subcellular elements regarding drug release from the carrier. The obtained release results indicate a >4-fold increase in the amount of drug released from the carrier in conditions of a slightly lower pH environment (70 %), compared to neutral pH (15 %). This represents a promising potential for using the material as an intelligent drug delivery system (DDS).

Review of the wolf spider genus Halocosa Azarkina & Trilikauskas, 2019 from China (Araneae, Lycosidae).

The wolf spider genus Halocosa Azarkina & Trilikauskas, 2019 from China is reviewed, including two species: H.cereipes (L. Koch, 1878) (♂♀) and H.hatanensis (Urita, Tang & Song, 1993) (♂♀). Both species are restricted to northern China, with H.cereipes recorded from China for the first time. Halocosajartica (Urita, Tang & Song, 1993), syn. nov. is synonymized with H.hatanensis (Urita, Tang & Song, 1993). Detailed species descriptions, along with morphological photos, genitalia illustrations, SEM photos of the bulbs and photos of live specimens are also presented.

A green approach to improve antibacterial properties of PVC/PVDF film doped by silver nanoparticles via nanosecond laser ablation for wound healing application

Nanocomposite films of (30% PVC/70% PVDF) blend containing silver nanoparticles were synthesized via pulsed laser ablation route (PLA). Changes in physical characterization of PVC/PVDF blend before and after the incorporation of AgNPs have been studied. FTIR results confirms the interaction between AgNPs and PVC/PVDF. XRD results obtain the existence of peak at 38.42̊ in sample PVC/PVDF/Ag4 which confirm the embedded AgNPs in the high concentration. SEM photos confirm the distribution of silver nanoparticles on the surface of the sample in spherical shape which approved the dispersion of silver nanoparticles in PVC/PVDF blend. The inhibitory zone diameters observed for PVC/PVDF/Ag4 against Escherichia coli, Klebsiella pneumonia, Staphylococcus aureus, and Bacillus cereus were recorded as 11 ± 1, 10 ± 1, 15.7 ± 0.6, and 17.7 ± 0.6, respectively. PVC/PVDF/AgNPs nanocomposite film could be suggested for biomedical applications such as wound healing products.

One-Step Preparation of Both Micron and Nanoparticles.

The complex materials comprised of both micron and nanometer-sized particles (MNPs) present special properties different from conventional single-size particles due to their special size effect. In this study, the MNPs could be simultaneously synthesized in a one-pot medium by soap-free emulsion polymerization, without harsh preparation conditions and material waste. In the whole process, the amphipathic siloxane oligomers would migrate to the mixed monomer droplet surface to reduce the surface energy of the system and further complete hydrolysis-condensation to obtain the SiO2 shell at the water-oil interface. On the one hand, the mixed monomers inside the above shell would migrate outward driven by the capillary force generated at the shell mesopore and be further initiated by the water-soluble initiator potassium persulfate (KPS), resulting in the formation of bowl-shaped micron particles with "lunar surface" structure. On the other hand, the residual mixed monomers dissolve in water and could be polymerized by initiating free radicals in the water phase to obtain popcorn-like nano-sized particles. The above two particles are clearly displayed in the SEM photos, and the DLS characterization further shows that the sizes of two particles are concentrated at 1.4 μm and 130 nm, respectively. Interestingly, the uniformity of obtained particles has a great relationship with the added amount of BA, and the perfect MNPs would appear when the St/BA feed mass ratio is 1:2. Moreover, the MNPs exhibit film-forming property, and the SiO2 component is evenly distributed in the formed coating. Thus, this study is not only beneficial to the theoretical research of soap-free emulsion polymerization but also to the application of multifunctional coatings.

SUPERSOFT SPONGE-LIKE CRYOGEL AS AN IMPLANT TO TREAT GLIOBLASTOMA

Abstract AIMS Create cylindrical cryogels with well-defined size. Investigate clemastine drug loading capicaty and drug release patterns. Investigate in vitro and in vivo safety and antitumor efficacy. METHOD A 3D printed template was designed and printed to make cylindrical shape cryogels. The morphology of cryogels was characterized by bright field photos, SEM, FTIR and confocal microscopy photos. The mechanical property was evaluated by uniaxial compression tests. The orthotropic glioblastoma tumor model was established by engrafting BT12 human glioblastoma stem cells intracerebrally into immunocompromised nude mice. The tumor was surgically removed after two weeks and the cryogel was implanted into the resection cavity. Animals were euthanized after two weeks, and their brains were collected for the immunohistochemistry. RESULTS Cylindrical cryogels were prepared to exactly fit the biopsy resection cavity in the mouse glioblastoma tumor resected model. The macropore structure in the cryogel was observed under confocal microscopy. Young’s modulus of the cryogel was only 1.6 kPa. The loading capacity of clemastine in one cryogel was more than 100 μg. Clemastine could be sustained released for around a week. In vitro cell viability studies showed that empty cryogels were not toxic to the tumor cells and drug loaded cryogels killed the tumor cells in a time and concentration dependent manner. In vivo studies further confirmed that cryogels could be safely implanted into the brain. Although the implantation of clemastine loaded cryogels did not prevent the growth of the primary tumor, it reduced the amount of invasion tumor cells compared with the mice only resected the tumor. CONCLUSION Cryogels were easily created by the 3D printed templates. The soft material avoided mechanical mismatch with the brain tissue. The cryogel did not show any toxicity in in vitro and in vivo studies, which indicated it would be a promising material to be implanted into the brain.

Morphology and surface structure of eggs and fırst instar larvae of Coccinella septempunctata (Linnaeus, 1758) (Coleoptera: Coccinellidae)

The seven-spotted ladybug, Coccinella septempunctata (Coleoptera: Coccinellidae) L., is a polyphagous predatory species that feeds on many species of aphids and some soft-bodied insects in both larval and adult stages. For this reason, C. septempunctata L. (Coccinellidae) is very important in biological control. In this study, the egg structure and first larval period of C. septempunctata were examined using stereomicroscopy and scanning electron microscopy. The first larvae that emerge from C. septempunctata eggs are dark brown and have 3 pairs of legs. The abdomen consists of 8 segments. In SEM photographs, star-shaped extensions were observed on both sides of the strip on the dorsal surface of the thorax and abdomen of the larvae. Large stigma openings were found at equal intervals on the side of the abdomen. C. septempunctata eggs are clear and oval, appearing elliptical dorsally and ventrally and slightly rounded at both ends. The egg and larval structure of the invasive species C. septempunctata is described in detail.

Preparation of Jackfruit Artocarpus Heterophyllus Seed Starch-Grafted Polyvinyl Acetate by Emulsion Polymerization

Abstract Petrochemical-based materials are depleting for the past decades and alternative methods to replace them are being studied over the years. This includes a wide range of probable applications such as adhesive industry. Starch, in its native form, possesses inadequate bond strength and viscosity. The said properties limit the possible applications of starch thus improvement should be employed. Jackfruit seed (JFS) starch is a viable substitute for other starches that is commonly used in the industry. This research developed a starch grafted polyvinyl acetate formula that can be used as an alternative to non-renewable and food consumable resources. Parameters such as monomer/starch ratio, temperature, and amount of initiator were observed and how it affected the graft percent, shear strength, and viscosity of the samples. This process was conducted via emulsion polymerization using PPS as initiator and SDS as emulsifier, Ethanol was also utilized to wash away homopolymers. Each run was done under ambient conditions. The samples were triplicated in the software to ensure the data credibility. From the statistical analysis, it was concluded that all three parameters which are temperature, monomer/starch ratio, and initiator amount were all significant. The appearance of 1735 cm−1 band in FTIR spectrum of the grafted starch and the visible roughness in the spherical-shaped granules in SEM photographs indicated that the VAc has been successfully grafted onto jackfruit starch. DSC analysis showed that Tg of starch-g PVAc was shifted to a little higher value as compared to Tg of native jackfruit starch which suggests that material can be used in a wider temperature range.

The impact of spent fluid catalytic cracking catalyst on the selected mechanical and physical performances of cement mortars

This paper presents the results of research aimed for evaluating the impact of applicability of spent fluid catalytic cracking catalyst as a substitute of 20, 40, 60 and 80% of cement, by mass, in cement mortars on their selected mechanical and physical performances. It was demonstrated that substitution of 20% of cement mass with spent catalyst enhanced mortar’s compressive strength for 16.7%. Further addition of spent catalyst tended to decrease strength, whilst, simultaneously, rose the values of capillary absorption and water absorptivity because of deterioration of cement matrix structure, documented by SEM photos. Based on the research and literature data, it was proved that spent cracking catalyst might be a promising additive to cement in the amount not exceeding 40% of its mass considering its pozzolanicity

Off-site production of plasma-activated water for efficient disinfection: The crucial role of high valence NOx and new chemical pathways

Efficient disinfection of pathogens is a critical concern for environmental disinfection and clinical anti-infective treatment. Plasma-activated water (PAW) is a promising alternative to chemical disinfectants and antibiotics for its strong disinfection ability and not inducing any acute toxicity. Previous plasma sources are commonly placed near or fully in contact with water as possible for more efficient activation, but the risk of electrode corrosion and metal particle contamination of water threatens the safety and stability of PAW. In this work, plasma-activated gas (PAG) rich in high-valence NOx is generated by a hybrid plasma configuration and introduced into water for off-site PAW production. It is found that plasma-generated O3 dominates the gas-phase reactions for the formation of high-valence NOx. With the time-evolution of O3 concentration, the gaseous NO3 radicals are produced behind N2O5 formation, but will be decomposed before N2O5 quenching. By decoupling the roles of gaseous NO3, N2O5, and O3 in the water activation, results show that short-lived aqueous species induced by gaseous NO3 radicals play the most crucial role in PAW disinfection, and the acidic environment induced by N2O5 is also beneficial for microbial inactivation. Moreover, SEM photographs and biomacromolecule leakage assays demonstrate that PAW disrupts the cell membranes of bacteria and thus achieves inactivation. In real-life applications, an integrated device for off-site PAW production with a yield of 2 L/h and a bactericidal efficiency of >99.9 % is developed. The PAW of 50 mL produced in 3 min using this device is more effective in disinfection than 0.5 % NaClO and 3 % H2O2 with the same bacterial contact time. Overall, this work provides new avenues for efficient PAW production and deepens insights into the fundamental chemical processes that govern the reactive chemistry in PAW for environmental and biomedical applications.

Seasonal fluctuations of heavy metal accumulation and gastrointestinal helminth induce oxidative stress and histological lesions in resident catfish Clarias gariepinus

The exposure of the African catfish (Clarias gariepinus) to various environmental contaminants leads to physiological and histological alterations. Therefore, the study aimed to assess the impact of seasonal variations of ecological contaminants as external stressors and internal stressors via helminth infections on oxidative stress and histopathology in resident C. gariepinus at EL-Salam Canal, Egypt. Seasonal water and sediment samples were collected to assess physicochemical parameters and heavy metals. The length, weight, and sex were recorded for each fish sample. The gastrointestinal tract was dissected from the visceral cavity, and the helminths were extracted and identified using SEM photos based on their morphological characteristics. The parasitic dominance in the gastrointestinal helminths was calculated. The heavy metal concentrations, bioaccumulation (BAF), and biosedimentation (BSF) factors were considered in the muscles and intestine. Specimens of muscles and intestines were removed to determine oxidative status. In addition, pieces of skin, muscles, stomachs, and intestines were subjected to light microscopy to determine the alterations. The calcium, magnesium, and potassium levels were within safe limits. Sulfate levels consistently remained below the maximum permissible thresholds throughout the seasons. Among the heavy metals examined, the highest accumulation was found in the intestinal tissues of C. gariepinus, while muscle tissues showed lower levels. The variability in metal concentrations across water, sediment, muscles, and intestines underscores the different capacities of these environments to accumulate heavy metals. The elevated metal levels in fish tissues raise concerns about potential health risks for humans who consume contaminated fish, highlighting significant bioaccumulation within the food chain. The result indicated that Cu in the sediment samples was associated with parasite abundance. The dual stress from environmental pollutants and parasitic infections exacerbates oxidative stress and causes notable histopathological changes in the tissues of the catfish. These results highlight the intricate interplay between external and internal stressors, emphasizing the need for continuous monitoring and management of aquatic ecosystems to safeguard the health of resident fish populations. It provides insight into how these factors affect fish health.

Coating effect of polyurethane-layered double hydroxide nanocomposite on steel

The motivation behind this work is the preparation of polyurethane-magnesium aluminum layered double hydroxide (PU-LDH) nanocomposite and its application as a coating for steel protection. The coating was prepared with different doses of LDH, ranging from 0 to 2% of the coating weight. The effect of different concentrations on the mechanical, adhesion, and surface properties of PU coating is studied. Firstly, LDH was prepared via the coprecipitation process and then distributed in PU matrix. The nanocomposites were then crosslinked in the form of coating layers on steel. The preparation of the thermally stable crystalline LDH nanoparticles with 89 nm particle size was confirmed by FTIR, XRD, DLS, and TGA. SEM photos showed the dispersed and intercalated structure. The coating characteristics demonstrate that addition of LDH decreased the drying time and increased the dry film thickness of PU up to 1.5% due to the crosslinking between the large surface area nanofiller and polyurethane matrix. Furthermore, the prepared LDH nanofiller increased the adhesion strength, impact resistance, abrasion resistance, modulus, and flexibility of PU due to the strong polymeric network structure. The 2% nanocomposite coating shows poor properties due to the excess concentration and heterogeneous dispersion of nanoparticles within the PU polymer. The resistance to fire and some chemicals was supported by the thermally and physically stable LDH nanoclay. The former characterizations state that the proposed PU-LDH nanocomposite is an enhanced and applicable coating.

Chitosan Based Zinc and Copper Nanoparticles: Synthesis, Characterization and Antibacterial Activity Investigation

Chitosan biopolymer has been used as a key supporting material for the synthesis of metallic nanoparticles (MNPs) due to its exceptional qualities, which include good capping and stabilizing capabilities, biocompatibility, biodegradability, eco-friendliness, polycationic and non-toxicity. In this study, chitosan-based metal nanoparticles, such as copper nanoparticles (Chi-Cu NPs) and zinc nanoparticles (Chi-Zn NPs) have been synthesized, characterized and checked for their bacteriological properties. The solution casting method has been employed to produce metal nanoparticles based on chitosan. FTIR, TGA, and SEM analysis were employed to characterize the produced nanoparticles. The produced materials are nanomaterials with a size range of 1-100 nm, as demonstrated by the SEM photograph. The generated nanoparticles showed increased antimicrobial activity. Chi-Zn NPs have zones of inhibition of 38, 31, 30 and 39 and Chi-Cu NPs have zones of inhibition of 32, 36, 37 and 32 mm against Pseudomonas aeruginosa, Salmonella bovismorbificans, Salmonella typhi and Escherichia coli bacteria, respectively. Whereas the standard medication kanamycin have zones of inhibition 22, 22, 20 and 20 against those bacteria, respectively. Journal of Engineering Science 15(1), 2024, 45-57

Effect of heat treatment on chemical durability and TL dosimetric properties of Na2O-SrO-B2O3 glass system

Na2O-SrO-B2O3 glass system prepared by the known melting-quenching method was applied to a progressive heat treatment (HT) at 600 °C for 4, 6, 8 and 10 h. Glass (G) and its corresponding heat treated (HT) samples were characterized by density, molar volume and XRD technique that revealed the complete amorphous structure of the glassy matrix and the coexistence of two crystalline phases in the corresponding glass ceramics; monoclinic phase of NaSrBO3 and the triclinic phase of sodium strontium pentaborate Na3SrB5O10. Testing chemical durability of G and HT samples at 95 °C for 24 h, revealed higher chemical stability in aqueous (H2O) and acidic (H2SO4) solutions, while the highest leachability was detected in the alkaline medium (NaOH). pH of leaching solution was found to control the leaching process and displayed rising behavior with time of immersion. The progressive rising of leaching solution temperature; 25, 40, 60 and 95 °C, revealed a quiet leachable enhancement as well. SEM photographs represented rough and heterogeneous surface morphology with continual leaching and the formation of colloidal layers at the later stages of corrosion.The TL-dosimetric properties indicated extremely higher thermoluminescence properties of HT samples than the untreated glass. The analysis of the exhibited TL signals revealed the composition of the glow curves of the treated and untreated samples of eight TL components. The obtained results recommend the acceptable chemical durability of the heat treated samples especially in the neutral medium that displayed no more than 8.5% leachability rate yearly, besides their promising TL-dosimetric features, accordingly their possible application in the field of radiation dosimetry.

A coral-like skeleton carbon aerogel achieves good mechanical and thermal insulation properties

A coral-like network carbon aerogel was synthesized by introducing acid-modified carbon nanofibers (a-CNF) into phenolic (PR) aerogel through chemical grafting, followed by high-temperature carbonization. The bonding interaction between a-CNF and PR was analyzed by FT-IR spectroscopy. The microstructure of a-CNF/PR composite aerogel (a-CNF/PRA) was studied by SEM and pore structure analysis. The results showed that introducing 5 wt% of a-CNF was most favorable for forming a porous network of a-CNF/PRA. SEM photographs and pore structure analysis indicated that a-CNF/C composite aerogel (a-CNF/CA) developed a stable porous skeletal structure during carbonization. TEM images revealed that the complete porous skeleton consisted of a-CNF encapsulated by carbon layers. The carbonization shrinkage of a-CNF/CA was only 26.53% due to the presence of a-CNF as the skeleton support. Compared to carbon aerogel, a-CNF/CA exhibited lower density (0.072 g cm−3), thermal conductivity (0.0452 W m−1 K−1), and higher compressive strength (up to 3.26 MPa) up to 3.26 MPa than that of carbon aerogel (1.21 MPa). These findings confirmed the excellent mechanical and thermal insulation properties of a-CNF/CA.

Chitons of the genus Cryptoplax (Mollusca: Polyplacophora) from the Spratly Islands, South China Sea.

Four species of the polyplacophoran genus Cryptoplax were identified among chiton samples collected from the Spratly Islands (Truong Sa), South China Sea. Among them, one is described as new species C. acerocostata n. sp.. The other three species, namely, C. larvaeformis (Burrow, 1815), C. brunoi Saito, 2023, and C. burrowi (E. A. Smith, 1884), are reported for the first time from the Spratly Islands. Color and SEM photographs of their features are given for all four species.

The performance of hydrophilic moieties in synthesized fluorinated cationic surfactants on corrosion inhibition of carbon steel pipelines

Compared with traditional hydrocarbon surfactants, fluorinated surfactants exhibit unique characteristics such as reduced surface tension, enhanced efficacy in reducing interfacial tension, dual hydrophobic and oleophobic nature, increased thermal stability, and superior chemical resistance. These characteristics make them a favorite material for many kinds of applications. This study aims to highlight the synthetic route for three novel cationic fluorinated surfactants (CFS) and applied them in the oilfield as corrosion inhibitors. Characterization of the prepared surfactants took place using different spectroscopic techniques. The influence of hydrophilic moieties on the micellar characteristics of ionic surfactants that have the same hydrophobic fluorinated chains are investigated in this research. Also, an evaluation of the influence of these groups on thermodynamic parameters was carried out.The metal corrosion inhibition efficiency of the CFS was studied in acidic medium by three different techniques, including potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and weight loss procedures, at three different temperature ranges (25, 40, and 60 °C).The achieved results displayed the inhibition efficiency of the metal corrosion that was elevated by increasing both the CFS's concentration and the applied temperature values. The highest level of inhibition, reaching 97.48 %, was achieved at a concentration of 700 parts per million (ppm) and a temperature of 60 °C. Furthermore, it was noticed that the charge transfer resistance value was raised; however, the constant phase element was decreased with increasing the CFS concentrations. The CFS regards an excellent and mixed-type corrosion inhibitor. The adsorption of CFS has agreed the Langmuir's adsorption isotherm and was related to chemisorption. SEM photos show a good CS surface in the presence of CFS versus the absence of them.

QbD-based formulation development of resveratrol nanocrystal incorporated into soluble mesoporous material: Pharmacokinetic proof of concept study

Resveratrol (RSV) has powerful antioxidant activities. However, the bioavailability is still limited due to low solubility and transport issues. Nanocrystal technology has been introduced to address these issues; however, the bulky formulation of the nanocrystal process through nanosuspension faces a big challenge in terms of stability and scale-up ability. This work aimed to enhance the bioavailability of RSV through nanocrystal formulation incorporated into soluble mesoporous carriers for superior solid-state stability and feasibility. This formulation was designed and developed rationally through scientific justification in the nanocrystal formulation along with quality by design paradigm. Box-Behnken design was applied to determine the optimized formulation based on the particle size and distribution, drug loading, zeta potential, and supersaturation parameters. The nanocrystal was formed through evaporation of drug, polymer, and surfactant in the solvent incorporated into mesoporous material. The nanocrystal was evaluated by vibrational spectroscopy, thermal analyses, and SEM and TEM photographs, followed by crystallinity evaluation. The results indicated that the factors only affected the particle size variation, zeta potential, drug loading, and the time to reach the supersaturation peak level. The optimized formulation was achieved by 68 % desirability value, producing 133.3 ± 1.2 nm particle size and −24.6 mV zeta potential. The physical and chemical evaluation characterization indicated no interaction between RSV and carrier. In addition, there was no difference in crystallinity between the RSV nanocrystal and native RSV. Moreover, the RSV nanocrystal improved the bioavailability nearly twice compared to the RSV suspension.

COMPLEX OF Co(II) WITH LIGAND 2,2’-BIPYRIDINE AND ANIONIC TRIFLUOROACETATE: SYNTHESIS, PHYSICAL PROPERTY, STRUCTURAL ANALYSIS AND ITS ANTIBACTERIAL ACTIVITY

The complex containing Co(II), bipyridine (bipy), and trifluoroacetate (TFA) was prepared and characterized. The metal content, conductance, and TGA-DTG analysis estimate the formula of [Co(bipy)3](CF3COO)2.5,5H2O. The magnetic property shows the moment of 4.2-5.3 BM which should correspond to the three unpaired electrons with the typically strong orbital contribution in cobalt(II). The UV-VIS spectral profiles indicate the three possible spin-allowed transitions of the corresponding quartet states. The characteristic vibration modes of bipy and TFA confirm the complex formula. The SEM photographs support the crystalline particle size, and the corresponding EDX signifies the existence of all elemental contents. The powder XRD profile has been refined according to the Le Bail method of the Rietica program, and the result suggests being a structurally monoclinic system of space group C2/c. This complex exhibits a weak inhibition against S. aureus and E. coli bacterial activity.

Tuning of structural, magnetic, and optical properties of ZnO nanoparticles by Co and Cu doping

Undoped, Cu, and Co-doped ZnO nanoparticles were synthesized by a simple co-precipitation method. We studied the structural, chemical, magnetic, and optical properties of synthesized nanoparticles by using X-ray Diffraction, Fourier Transform Infrared, Scanning Electron Microscopy, Vibrating-Sample Magnetometer, and UV–VIS spectroscopy. The X-ray Diffraction analysis discovers the crystalline hexagonal wurtzite structure and confirms the incorporation of Cu2+ and Co2+ in the ZnO lattice. The SEM photographs show that the nanoparticles are agglomerated, and the grain size of pure ZnO is decreased upon doping, showing inhibition of grain growth through doping. From VSM the coercivity and saturation magnetization of Co-doped (0.0189 emu/g and 84.044Oe) is higher as compared to pure and Cu-doped ZnO. The energy gap of doped and un-doped nanoparticles determined from the absorption spectrum indicates that it increases by doping of Copper and cobalt.