Wet Chemical Precipitation Route Research Articles

Aluminium Doped Cerium Oxide as an Efficient Nanophotocatalyst for the Elimination of Rhodamine B Dye Present in Water

The photodegradation efficiency of rhodamine B (RhB) dye present in water using aluminium-doped CeO2 (Ce1-xAlxO2-δ; x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5) nanoparticles was studied in this work. The synthesis of nanoparticles was done by simple wet chemical precipitation route. The photochemical characteristics of Al doped CeO2 was studied by UV-visible (UV) and photoluminescence (PL) techniques. The photocatalytic removal of RhB dye was studied using the above nanomaterials as photocatalysts and the degradation efficiency was optimized by varying the pH and the concentration of dye solution under UV light. Among the samples studied, 0.02 g of sample with the composition of Ce0.50Al0.50O2- δ exhibited a higher photocatalytic degradation efficiency of 70.94% against RhB dye having concentration of 0.05 g/L at the pH of 11 under UV irradiation for 60 min at room temperature.

Hydroxyapatite nanoparticles synthesized with a wide range of Ca/P molar ratios and their structural, optical, and dielectric characterization

Hydroxyapatite (HAp) nanomaterials have been synthesized via wet-chemical precipitation route with Ca/P molar ratios of 1.40, 1.60, 1.67, 1.80 and 2.00. These samples have been characterized using scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, Fourier transform-infrared spectroscopy (FT-IR), ultraviolet–visible (UV–vis) diffuse reflectance spectroscopy (DRS), X-ray powder diffraction (XRPD), Rietveld refinement and dielectric spectroscopy. Micrographs from SEM showed that the calcined HAp particles were spherical in shape and they were highly agglomerated. The chemical composition derived from EDX was in good accordance with the theoretical Ca/P ratio. FT-IR spectroscopy revealed the characteristic functional groups: PO43− and OH−. Certain peaks were observed in the diffuse reflectance spectrum which is argued to originate from O2− → Ca2+ and O2− → P5+ charge transfer transitions. Phase analysis showed the existence of single pure HAp (\(\mathrm{P}{6}_{3}/\mathrm{m}\)) only for samples with Ca/P = 1.6 and 1.67. However, HAp with Ca/P = 1.4 had tricalcium phosphate (TCP, Ca3(PO4)2) as the secondary phase, while Ca/P = 1.8 and 2.0 had CaCO3 as the secondary phase. Thermograms displayed multiple steps indicating the degradation of secondary phases at higher temperatures. Further, XRD analysis of post-TGA samples revealed that there was no change in the space group symmetry; however, the phase identified was Ca5(PO4)3(CO3)0.01(OH)1.3. The dielectric constant (\({\varepsilon }^{^{\prime}}\)) and dielectric loss (\(\mathrm{tan}\delta\)) decline with enhancing frequency corresponding well with space-charge and ionic-type polarization behaviour. The ac electrical conductivity enhanced with increasing frequency obeying the Jonscher universal power law.

Pyrrol-Anthracene: Synthesis, Characterization and Its Application as Active Material in Humidity, Temperature and Light Sensors

This work reports on the synthesis of small molecular semiconductor 2-(1H-pyrrol-1-yl)-anthracene-9,10-dione (PAD) via wet chemical precipitation route method for its possible potential applications in sensors. Thin film characterization of the synthesized PAD is carried out by studying its surface morphology, bond dynamics, and optical properties. For studying sensing characteristics of the PAD, its 100 nm thick film is thermally deposited on pre-patterned silver (Ag) electrodes over glass substrate having ~45 µm inter-electrode gaps to prepare Ag/PAD/Ag sensor. The effects of humidity (%RH), temperature (T), and illumination of light (Ev) on the fabricated Ag/PAD/Ag sensor are studied by changing one of the three (%RH, T, and Ev) parameters at a time and measuring the corresponding variations in capacitance (C) and capacitive reactance (X) of the device. As C and X also depend on frequency, sensing properties of the Ag/PAD/Ag sensor are measured at two different frequencies (120 Hz and 1 kHz) to find the optimum sensitivity conditions. To investigate reproducibility and repeatability of Ag/PAD/Ag sensor, each measurement is taken several times and also hysteresis loops of %RH vs. C are plotted at 120 Hz and 1 kHz to find the percent errors in each cycle of measurements. The sensor is active to sense humidity, temperature, and illumination within a broad range, i.e., from 15–93%RH, 293–382 K, and 1500–20,000 lx, respectively. Other key parameters of the sensor i.e., the humidity response time (TRes) and recovery time (TRec), are measured, which are 5 and 7 s, respectively, whereas for light sensing the values of TRes and TRec are measured to be 3.8 and 2.6 s, respectively. The measured values of TRes and TRec for the fabricated Ag/PAD/Ag sensor are shorter and better as compared to those of previously reported for similar kind of small molecular based sensors. The sensing properties of Ag/PAD/Ag device exhibit the potential of PAD for humidity, temperature, and light sensing applications.

Cuprous Oxide Nanoparticles: Synthesis, Characterization, and Their Application for Enhancing the Humidity-Sensing Properties of Poly(dioctylfluorene).

In this paper, we report on the synthesis—via the wet chemical precipitation route method—and thin film characteristics of inorganic semiconductor, cuprous oxide (Cu2O) nanoparticles, for their potential application in enhancing the humidity-sensing properties of semiconducting polymer poly(9,9-dioctylfluorene) (F8). For morphological analysis of the synthesized Cu2O nanoparticles, transmission electron microscope (TEM) and scanning electron microscope (SEM) micrographs are studied to investigate the texture, distribution, shape, and sizes of Cu2O crystallites. The TEM image of the Cu2O nanoparticles exhibits somewhat non-uniform distribution with almost uniform shape and size having an average particle size of ≈24 ± 2 nm. Fourier transformed infrared (FTIR) and X-ray diffraction (XRD) spectra are studied to validate the formation of Cu2O nanoparticles. Additionally, atomic force microscopy (AFM) is performed to analyze the surface morphology of polymer-inorganic (F8-Cu2O) nanocomposites thin film to see the grain sizes, mosaics, and average surface roughness. In order to study the enhancement in sensing properties of F8, a hybrid organic–inorganic (F8-Cu2O) surface-type humidity sensor Ag/F8-Cu2O/Ag is fabricated by employing F8 polymer as an active matrix layer and Cu2O nanoparticles as a dopant. The Ag/F8-Cu2O/Ag device is prepared by spin coating a 10:1 wt% solution of F8-Cu2O nanocomposite on pre-patterned silver (Ag) electrodes on glass. The inter-electrode gap (≈5 μm) between Ag is developed by photolithography. To study humidity sensing, the Ag/F8-Cu2O/Ag device is characterized by measuring its capacitance (C) as a function of relative humidity (%RH) at two different frequencies (120 Hz and 1 kHz). The device exhibits a broad humidity sensing range (27–86%RH) with shorter response time and recovery time, i.e., 9 s and 8 s, respectively. The present results show significant enhancement in the humidity-sensing properties as compared to our previously reported results of Ag/F8/Ag sensor wherein the humidity sensing range was 45–78%RH with 15 s and 7 s response and recovery times, respectively. The improvement in the humidity-sensing properties is attributed to the potential use of Cu2O nanoparticles, which change the hydrophobicity, surface to volume ratio of Cu2O nanoparticles, as well as modification in electron polarizability and polarity of the F8 matrix layer.

Influence of RE (Pr3+, Er3+, Nd3+) doping on structural, vibrational and enhanced persistent photocatalytic properties of ZnO nanostructures

Rare earth (RE- Pr, Er and Nd) doped ZnO nanostructures were prepared through simple wet chemical precipitation route. The RE doping induced interesting morphological transition from spherical to flower like structures were analyzed. The X-ray diffraction (XRD) measurements revealed that the prepared materials were of highly crystalline in nature and RE dopant ions did not altered the crystal structure of ZnO. The microstrain of ZnO was altered with respect to the nature of dopants. In the case of the Pr doped ZnO, X-ray photoelectron spectroscopy (XPS) analysis confirmed that the dopant (Pr) ions successfully substituted in the ZnO lattice. Raman spectra revealed RE doping induced lower energy side shift and variation in intensity of the peaks related to the characteristic phonon modes of ZnO. In the case of Nd doped ZnO nanostructures, dopant induced suppression in classical Raman modes and evolution of multiphonon related modes were identified. Optical diffuse reflectance spectral (DRS) measurements, along with the characteristic excitonic band of ZnO, other bands associated to the transitions of 4f energy levels related to the RE ions were observed. The partially filled 4f orbitals led to the enhanced photocatalytic activity in RE doped ZnO nanostructures. The observed enhanced photocatalytic activity in RE doped ZnO when compared to bare ZnO was discussed. The decolorization efficiency of MB ensued the following order 96 > 94 > 86 > 78% for ZnErO, ZnNdO, ZnPrO and ZnO, respectively.

Whey Proteins-Zinc Oxide Bionanocomposite as Antibacterial Films.

The use of toxic crosslinking agents and reagents in the fabrication of hydrogels is a frequent issue which is particularly concerning for biomedical or food packaging applications. In this study, novel antibacterial bionanocomposite films were obtained through a simple solvent casting technique without using any crosslinking substance. Films were made from a flexible and transparent whey protein matrix containing zinc oxide nanoparticles synthesised via a wet chemical precipitation route. The physicochemical and functional properties of the ZnO nanoparticles and of the composite films were characterised, and their antibacterial activity was tested against S. epidermidis and E. coli. The synthesised ZnO nanoparticles had an average size of about 30 nm and a specific surface area of 49.5 m2/g. The swelling ratio of the bionanocomposite films increased at basic pH, which is an appealing feature in relation to the absorption of chronic wound exudate. A n-ZnO concentration-dependent antibacterial effect was observed for composite films. In particular, marked antibacterial activity was observed against S. epidermidis. Overall, these findings suggest that this novel material can be a promising and sustainable alternative in the design of advanced solutions for wound dressing or food packaging.

Enhanced antifouling property of polydimethylsiloxane-CuO nanocomposite in marine environment

Increased adhesion and biofilm formation by marine microalgae as well as inhibition of settlement of invertebrate larval forms on polydimethylsiloxane (PDMS) foul release coatings is a challenge to overcome. Copper oxide nanoparticles (CuO-NP) were synthesized by a wet chemical precipitation route and incorporated into PDMS foul release surfaces to improve its anti-microfouling nature. In situ antifouling performance of PDMS-CuO nanocomposite (NC) was evaluated in coastal waters and compared with plain PDMS surface. Adhesion and settlement of microalgae and macrofoulers and their succession were monitored for 7 and 90 days respectively. Plain PDMS surfaces were abundantly colonized by microalgae (1.3 × 103 cm−2), wherein significant (p < 0.05) reduction (1.76 × 102) was observed with PDMS-CuO NC. In addition, CuO reinforcement significantly (p < 0.05) reduced the biofouling load and surface area coverage upto 1.6 ± 0.22 Kg m−2 90 day−1 and 27.5 ± 4.5% respectively, whereas plain PDMS surfaces experienced 10.6 ± 1.5 Kg m−2 90 day−1 and 89.6 ± 7.96% respectively. Incorporation of CuO nanoparticles as nanofillers into PDMS matrix offers a promising antifouling alternative to inhibit algal fouling as well as larval settlement by imparting toxicity at the surface through release of metal ions.

RETRACTED ARTICLE: Synthesis and characterization of magnetite/hydroxyapatite nanoparticles for biomedical applications

During the last few decade, magnetite/hydroxyapatite nanoparticles have attracted much attention for its potential applications in the field of medicine and controlled drug delivery. In the present work, we have intended and synthesized, magnetite/hydroxyapatite nanoparticles by wet-chemical precipitation route. The thermal decomposition of the prepared sample was carried out by Thermogravimetric and Differential Scanning Calorimetry (TG/DSC) analysis upto 1000 °C, it showed that the sample was stable up to 919.2 °C. The phase formation, functional groups, morphology and magnetic property of as-prepared and annealed samples were characterized using X-ray diffraction (XRD), Fourier Transform Infrared (FTIR), micro Raman, Field Emission Scanning Electron Microscopy (FE-SEM), Transmission electron microscopy (TEM) and vibrating-sample magnetometer (VSM). By adopting Scherer method detailed structural analysis like the crystallite size, strain, dislocation density, lattice parameter, unit cell volume, surface area and fraction of crystallinity were calculated for as-prepared and annealed HAP samples. The average crystallite size of the as-prepared, annealed at 700 °C, 800 °C and 900 °C are 39, 46, 51 and 65 nm, respectively. The dislocation density, strain and surface area were decreased. FT-IR and Raman spectra showed both as-prepared and annealed samples possessed the characteristic bands of HAP. FE-SEM and TEM images depicted and confirmed the morphological characteristics of HAP. The VSM analysis confirmed that both as-prepared and annealed samples of HAP are in diamagnetic nature. The dielectric constant of as-prepared and annealed samples decreased with increase in annealing temperature whereas the conductivity increases with increase in frequency. The antibacterial property of apatite samples depending on the types of bacterial strains and also activity changed with the crystallite size.

Structural analysis and temperature dependent conductivity of LaxCu1-xO shrimp-like nanostructures synthesised via wet chemical precipitation

A series of well textured undoped and La-doped CuO (LaxCu1-xO, x = 0, 0.03, 0.06 and 0.10) nanostructures were synthesised via a low cost and facile wet chemical precipitation route. The structural, optical and temperature dependent electrical properties of the products were investigated and correlated. X-ray diffraction (XRD) showed formation of a pure phase of monoclinic CuO (undoped and 3–6 at.% La-dopped sample) and CuO-La2O2CO3 mixed phase in the higher doped sample (10 at.%). Scanning electron microscopy revealed shrimp like nanostructures of diverse sizes and aspect ratios for all the samples. The samples showed an optical absorption spectra with cut-off wavelengths lying in the visible spectral region. The temperature dependent electrical conductivity was measured and the trends depicted a typical semiconducting behaviour in all the samples. La doping of >3 at.% was associated with increased resistivity and premature levelling of the conductivity profiles at higher temperature. At 523 K, the electric field generated mobility and carrier concentration product values were observed to drop monotonously with doping. At room temperature the values were found to increase from 7.11 × 1014 (cm.s.V)−1 for the 0 at.% to peak at 2.16 × 1015 (cm.s.V)−1 for the 3 at.% and dropped to 8.95 × 1013 at 10 at.%. The conduction mechanism was explained on the basis of the hopping model.

Biosynthesis of Bonelike Apatite 2D Nanoplate Structures Using Fenugreek Seed Extract.

An innovative, biomimetic, green synthesis approach was exploited for the synthesis of humane and environmental friendly nanomaterials for biomedical applications. Ultrafine bonelike apatite (BAp) 2D plate-like structures were prepared using fenugreek seed extract during the biosynthesis wet-chemical precipitation route. The chemical analysis, morphology and structure of the prepared 2D nanoplates were characterized by inductively coupled plasma atomic emission spectroscopy (ICP-OES), electron microscopy (SEM and TEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. A 2D plate-like nanostructure of BAp with an average width (length) of 12.67 ± 2 nm and thickness of 3.8 ± 1.2 nm was obtained. BAp 2D crystals were tuned by interaction with the fenugreek organic molecules during the fabrication process. In addition to Ca and P ions, bone mineral sources such as K, Mg, Na, SO4 and CO3 ions were incorporated into BAp nanoplates using fenugreek seed extract. The overall organic molecule concentration in the reaction process increased the effectiveness of hydroxyl groups as nucleation sites for BAp crystals. Accordingly, the size of the biosynthesized BAp plate-like structure was reduced to its lowest value. Biosynthesis BAp 2D plate-like nanocrystals showed good viability and higher growth of MC3T3 osteoblast-like structures than that of the control sample. BAp 2D nanoplates prepared by a facile, ecofriendly and cost-effective approach could be considered a favorable osteoconductive inorganic biomaterial for bone regeneration applications.

Effect of zinc ions on the structural characteristics of hydroxyapatite bioceramics

Ionic substituted calcium phosphates have received much attention for their use as implant materials because of their ability to mimic natural hard tissues. In this work, the properties of hydroxyapatite ceramic doped with small amounts of zinc ions (5, 10, and 15 mol%) by using a wet chemical precipitation route were studied. XRD spectra revealed that adding zinc led to the development of a biphasic mixture composed of hydroxyapatite (HA) and β-TCP phases, which affected the morphology, crystallinity, and crystallite size of the precipitates. With increasing zinc ion substitution in the HA lattices, the degree of crystallinity of the powders reduces due to the additional formation of β-TCP phase. Slender, elongated, and highly agglomerated particles were observed for all synthesized powders. However, calcination at 700 °C caused the particles to become more spherical, having diameters ranging from 30 to 37 nm. An increase in the concentration of zinc ions promoted the β-TCP phase, which ultimately altered the lattice parameters of the HA structure and suppressed the growth of particles.

Capped and uncapped nickel tungstate (NiWO4) nanomaterials: A comparison study for anti-corrosion of copper metal in NaCl solution

We report for the first time, the role of capping agent and size effect of nickel tungstate (NiWO4) nanomaterials (NTN) in mitigation of copper corrosion in chloride medium. NTN were synthesized firstly, via a simple wet-chemical precipitation route without any capping agents (conventional process) and secondly with citric acid as capping agent, both in the presence of sodium tungstate (Na2WO4). Electrochemical analyses for corrosion protection have been tested and results indicated an improved corrosion protection of copper by the capped particles compared to the uncapped (conventional method) particles. A comparison was also made against Na2WO4 (a commercially available corrosion inhibitor).

HF-Free Synthesis of Li2SiF6:Mn4+: A Red-Emitting Phosphor.

Li2SiF6:Mn4+ was synthesized via a new HF-free synthesis route by a high-pressure/high-temperature doping experiment at 5.5 GPa and 750 °C. It is proven that the phosphor cannot be synthesized by the common wet-chemical precipitation route in aqueous HF. The sample was characterized by powder X-ray diffraction, EDX, and luminescence spectroscopy. At room temperature, Li2SiF6:Mn4+ exhibits seven emission lines with the strongest line at λmax ≈ 630 nm and a dominant wavelength of λdom ≈ 618 nm. The CIE coordinates are 0.688 and 0.312 for x and y, respectively. The compound shows a luminous efficacy of radiation (LER) of 218 lm Wopt-1, which exceeds the LER of current state-of-the-art red LED phosphor K2SiF6:Mn4+ by 7% due to a blue-shift of the emission. It reveals excellent thermal quenching behavior up to 125 °C.

Structural and morphological study of Zn0.9Mn0.05Fe0.05O synthesized by sol-gel wet chemical precipitation route

Transition metal substituted Zinc oxide (ZnO) has drawn a great deal of attention due to its excellent properties. Zn0.9Mn0.05Fe0.05O sample synthesized was by Sol-gel wet chemical precipitation route at temperature 350°C. The crystallinity and the structure of Zn0.9Mn0.05Fe0.05O was determined by X-ray diffraction by Cu-Kα radiations operated at 40kV and 35mA in the range of 20° to 80°. The pattern gets indexed in wurtzite (hexagonal) structure with lattice constants a=b=3.2525Å and c=5.2071Å and approves the single phase material with no impurity. The values of particle size assessed by Debye Scherer’s (DS) formula lie in the range of 13nm to 33nm indicating the nano-crystalline nature of the sample. The morphological analysis of the sample was performed by Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) measurements. The observed size of Zn0.9Mn0.05Fe0.05O nanoparticles by TEM micrograph exhibits the similar trend with the size calculated by Debye-Scherer formula. TEM image show the irregular shape of the nanoparticles and particle size lies in the range of 10-35nm. Similar to SEM image, the slight agglomeration of the nanoparticles have been observed from TEM.

Bioceramics synthesis of hydroxyapatite from red snapper fish scales biowaste using wet chemical precipitation route

Fish scales biowaste contain high collagens and calcium phosphates, therefore have considerable potential as raw material for value-added biomaterial such as hydroxyapatite (HAp). HAp is the main constituent component of hard tissue such as bone and teeth in the human body and is known as bioceramic materials. In this work, wet chemical precipitation method was used to syntesize HAp from Red Snapper Fish (Lutjanus campechanus) Scales. Two variations of calcination temperatures of 600°C (FHAp1) and 800°C (FHAp2) were conducted for 5 hours. The results showed calcium content from biowaste of red snapper fish scale was 83.62%. FTIR result shows that PO43-, OH-, and CO32- functional groups presence as indicates the formation of HAp. XRD result showed the degree of crystallinity for FHAp1 and FHAp2 were 75.52% and 79.20%, respectively. The degree of crystallinity is in accordance with ISO 13779-2:2000 standard in which the minimum degree of crystallinity of hydroxyapatite used for biomedical materials is 45%. Finally, Particle Size Analyzer (PSA) results show that the particle size distribution is evenly distributed, with the size of micro-scale hydroxyapatite particles, ranging from 5.76 μm to 132.64 μm.

Effect of concentration on nano hydroxyapatite powder by wet chemical precipitation route

Effect of concentration on nano hydroxyapatite powder by wet chemical precipitation route

Wet chemistry approach to the preparation of tantalum-doped hydroxyapatite: Dopant content effects

Tantalum-doped hydroxyapatite (Ta-doped HA) nanopowders with different Ta contents were synthesized by a wet-chemical precipitation route. The structure modification and charge compensation mechanism were investigated by various characterization techniques. Due to the smaller size of tantalum ions compared to the Ca2+ size, it was assumed that the tantalum ions occupy either the Ca2+ and/or the interstitial positions in the HA lattice, where the charge imbalance from to this substitution was compensated by the Ca2+ vacancies. From the XRD patterns, the as-synthesized nanopowders were poorly crystalline apatite in the absence and presence of different dopant contents. The hexagonal HA and tricalcium phosphate (β-TCP) phases as biphasic calcium phosphate mixtures were formed after heating at 900°C. In addition to the β-TCP phase, minor extra phases such as calcium oxide (CaO) and calcium pyrophosphate (Ca2P2O7) were identified from the HA decomposition. The FTIR results indicated that the decrease of structural hydroxyl groups depended on both tantalum oxyanions and carbonate contents. In the XPS profile, the Ta 4f peak of the doped sample could be decomposed into four main components, which showed different oxidation states for tantalum (TaO2 oxide). According to the TEM observations, the doped calcined powder at 900°C was composed of uniform nanoneedles with an average length and width of 120 ± 50 and 10 ± 5nm, respectively.

Synthesis and investigation of photonic properties of surface modified ZnO nanoparticles with imine linked receptor as coupling agent- for application in LEDs

Wet chemical precipitation route is developed for the synthesis of ZnO nanoparticles using a dipodal receptor as capping agent to control the size and shape of ZnO nanoparticles and also to passivate the surface defects. The capping of ZnO nanoparticles with dipodal receptor is characterized with NMR and IR spectroscopy. EDX analyses also confirmed the presence of organic receptors together with ZnO nanoparticles. The morphology and size of surface modified ZnO nanoparticles is checked by SEM, TEM and DLS spectroscopic techniques. The surface decorated ZnO nanoparticles demonstrate emission peak at 333 nm. The emission peak at 333 nm in case of surface capped ZnO demonstrate fewer surface defects present in comparison to their bulk counterpart, where blue, red, green, yellowish green emission peaks are present. The photophysical studies of ZnO nanoparticles are further carried in presence of metal ions where it is observed that the binding with Mn(II) result in increase in fluorescence intensity. The three fold increase in fluorescence intensity of ZnO nanoparticles in presence of Mn(II) can be utilized in case of lighting devices, where high quantum yield is desirable. To the best of our knowledge, this manuscript represents the first surface decorated ZnO nanoparticles for their application in lighting devices.

Synthesis, spray granulation and plasma spray coating of lanthanum phosphate nanorods for thermal insulation coatings

Nanorods of lanthanum phosphate obtained by a wet chemical precipitation route were granulated to obtain sizes in the range of 10–15µm by spray drying from aqueous slurry of 35wt% solid loading and 2wt% of PVA binder. The powders thus obtained displayed enhanced flowability and were plasma sprayed on to stainless steel substrates resulting in the formation of adherent coatings of 150–180µm thickness. These coatings were characterized using electron microscopy, X-ray diffraction analysis and Raman spectroscopy. X-ray analysis indicated phase instability of LaPO4 during plasma spraying resulting in the formation of oxy and polyphosphates of lanthanum (La2P4O13 and La3PO7). However, post deposition heat treatment of coated samples at 1100°C for 2h resulted in the reversible formation of stoichiometric lanthanum orthophosphate (LaPO4). Raman spectral analysis was used to confirm the phase structure of the coatings deposited at various plasma input powers. The coatings obtained were found to effectively lower the thermal conductivity of the substrates from ~24W/mK to less than 19W/mK (~10%) even at 200°C.

Magnetic and Optical Studies of 5%Mn and 5%Co Doped ZnO Synthesized by Sol Gel Wet Chemical Precipitation Route

Synthesis of Zn0.9Mn0.05Co0.05O was carried out using sol-gel wet chemical precipitation route. Synthesized product was characterized using by Transmission electron microscope (TEM) and FTIR spectroscopy. Analysis of TEM images reveals the particle size of Zn0.9Mn0.05Co0.05O in the range of 30-40 nm. FTIR spectroscopy results show hydroxyl and CO2 impurities in the sample. Magnetization with external field shows weak magnetic behavior of the sample at room temperature.