Browsing by Author "Arunadevi N"

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3-HYDROXY-2-NAPHTHOATE COMPLEXES OF TRANSITION METALS WITH HYDRAZINE - PREPARATION, SPECTROSCOPIC AND THERMAL STUDIES
(E-Journal of Chemistry, 2009-08-10) Arunadevi N; Vairam S
Reaction of hydrazine and 3-hydroxy-2-naphthoic acid with some transition metal ions forms two types of complexes: (i) [M(N2H4 ){C10H6 (3- O)(2-COO)(H2O)2 ] where M=Ni, Co, Cd and Zn, at pH 9 and (ii) [M(N2H5 )2{C10H6 (3-O)(2-COO)}2 ].xH2O where M=Ni & x =1; M=Co, Cd, Mn& x=3; and M=Zn, Cu & x =0 at pH 4. Analytical data confirms the compositions of the complexes. The acid shows dianionic nature in these complexes. The magnetic moments and electronic spectra suggest the geometry of the complexes. IR data indicates the nature of hydrazine and presence of water in the complexes. Simultaneous TG-DTA studies shows different thermal degradation patterns for the two types of complexes. The first type shows formation of no stable intermediates whereas the second type shows the respective metal hydroxynaphthoate intermediates. The final products in both the types are found to be metal oxides of nano size. XRD patterns show isomorphism among the complexes with similar molecular formulae.
THE ACID ADDUCTS HYDRAZINIUM 2-HYDROXYBENZOATE–2-HYDROXYBENZOIC ACID (1/1) AND HYDRAZINIUM 3-HYDROXY-2-NAPHTHOATE–3-HYDROXY-2-NAPHTHOIC ACID (1/1)
(Elsevier, 2012-02-07) Arunadevi N; Devipriya S; Vairam S
The title molecular salts, N2H5+·C7H5O3−·C7H6O3 and N2H5+·C11H7O3−·C11H8O3, are acid adducts containing a hydrazinium cation, one molecule of a deprotonated acid and one molecule of a neutral acid. The two compounds contain essentially identical hydrogen-bond networks between the hydrazinium cation and the acid molecules, which define closely comparable two-dimensional layers in the structures. The planes of the aromatic rings within both structures are approximately parallel and the layers are stacked with comparable intermolecular interactions.
THE ACID ADDUCTS HYDRAZINIUM 2-HYDROXYBENZOATE–2-HYDROXYBENZOIC ACID (1/1) AND HYDRAZINIUM 3-HYDROXY-2-NAPHTHOATE–3-HYDROXY2-NAPHTHOIC ACID (1/1)
(ActaCrystallographica Section C Crystal Structure Communications (ActaCrystallogr C), 2011-12-19) Arunadevi N; Vairam S
The title molecular salts, N2H5 + C7H5O3 C7H6O3 and N2H5 + - C11H7O3 C11H8O3, are acid adducts containing a hydraziniumcation, one molecule of a deprotonated acid and one molecule of a neutral acid. The two compounds contain essentially identical hydrogen-bond networks between the hydraziniumcation and the acid molecules, which define closely comparable two-dimensional layers in the structures. The planes of the aromatic rings within both structures are approximately parallel and the layers are stacked with comparable intermolecular interactions.
BIONANOCOMPOSITES FOR REJUVENATION OF HEAVILY CONTAMINATED ENVIRONMENT
(Elsevier, 2023-06-23) Arunadevi N; Jone Kirubavathy S
Treatment of air, land, and water is challenging for many engineers and scientists for environmental rejuvenation. A variety of methods have been explored for the removal of toxic materials. But the efficiency of these conventional methods is less. Among the different rejuvenation techniques, the adsorption process is used extensively due to its ease and low cost. After a successful search, bionanocomposites were found to be an effective and reliable environmental remediation tool. Bionanocomposites come under the class of advanced hybrid materials. They contain natural/synthetic degradable polymers along with nanomaterial. The nanocomposites play a significant role in wastewater treatment by removing contaminants such as dyes, organic compounds, and heavy metals. The attention toward bionanocomposites is owing to their physical and mechanical properties. This chapter focuses on cost-effective and efficient bionanocomposites for environmental rejuvenation.
BIOSYNTHETIC GREENER MOVE TOWARDS NANOSIZED SILVER BY DIOSPYROS MONTANA LEAF EXTRACT AND THEIR ANTIMICROBIAL AND ANTIOXIDANT ACTIVITIES
(Blue Eyes Intelligence Engineering & Sciences Publication, 2020-01-04) Kanchana P; Arunadevi N; Hemapriya V; Shanmuga Sundari S; Prabha Devi B
Synthesis of nanomaterials by eco-friendly method is being exploited by chemists because of several advantages over other conventional techniques. The current investigation reports the green approach for Diospyros Montana(DM) silver nanosized particles which has high antimicrobial and antioxidant activities. The synthesized nanosized particles were investigated by several techniques such as IR, Ultra violet, X-Ray Diffraction, Transmission Electron Microscope and AFM studies. Crystalline size of the silver nanoparticle is in the range of 47.05 nm which was clear from the powder X-rd studies. The silver nanoparticls prepared were tested for their antimicrobial potential against E.coli, B.subtilis, C.albicans and A.flavus species and was found to reveal excellent activity because of its volume ratio and high surface.The DPPH assy was used to find scavenging activity of free radicals. In this work we report the silver nanoparticles by aqueous Diospyros Montana leaf extract and its potential for free radical scavenging.
CITRUS LIMON ASSISTED GREEN SYNTHESIS OF MGO NANOPARTICLES: EVALUATION OF PHASE, FUNCTIONAL GROUPS, SURFACE MORPHOLOGY, THERMAL STABILITY AND COLLOIDAL STABILITY
(Elsevier, 2022-10-01) Vandamar Poonguzhali R; Srimathi M; Ranjith Kumar E; Arunadevi N; Hosam O, Elansary; Ashraf A A, Abdelback; Shaimaa A.M, Abdelmohsen
Citrus limon (the common lemon juice) assisted green combustion was used to create MgO nanostructures. The powder was heat treated for 3 h at 350 °C, and the as-synthesized and heat treated MgO nanostructures were tested by various techniques to investigate their phase composition, structure, thermal stability, colloidal stability, surface morphology, and antimicrobial activities. XRD was performed to study the single-phase cubic structure of MgO nanostructures, and the XRD results confirmed that the sizes of the MgO nanostructures are in the nanoscale range. The average crystallite sizes for as-synthesized and heat-treated samples are 7.8 nm and 19.2 nm, respectively. The functional groups in the experiment were examined using FTIR in the 400–4000 nm range. Thermal analysis of the MgO nanostructures were recorded through TG-DTA and the results confirm the MgO NPs thermally decomposed at 359.77 °C and 361.86 °C. The colloidal stability of the samples was tested using Zeta potential, it confirms that both samples are stable. The external morphology of as-synthesized and heat-treated samples were visualized through SEM. It confirms that the as-synthesized and heat treated MgO samples are nanostructures. The elemental analysis confirms the presence of Mg and O in both samples. The antimicrobial activity of MgO nanostructures tested by plate count mothed and the heat-treated sample exhibits noticeable antimicrobial performance against G-positive and G-negative bacteria.
DESIGNING AN ENHANCED SELF-SUPPORTED TRANSITION METAL COMPLEXES BASED ON ELECTROCATALYSTS FOR HYDROGEN EVOLUTION REACTION
(Taylor & Francis Online, 2023) Swathika M; Arunadevi N
Progressing efficient and low-cost catalysts to reduce overpotential within the hydrogen evolution reaction (HER) in large-scale production is highly desirable in the present era. The catalysts are accustomed to initiating an excellent approach to optimizing the electronic characteristics employed to boost their electrocatalytic production. In this article, we described the activity of transition-metal complexes with the nitrogenous analog of carbonic acid and naphthalene ring containing monocarboxylic acid to study hydrogen evolution reactions. The HER activity in transition metal complexes was varied through physicochemical and electrochemical properties. Density function theory (DFT) was calculated using the B3LYP hybrid functional and the basis set of 6-311 + G (d,p) to deliver the relevant frontier orbitals.
EVALUATION OF MICROSTRUCTURAL, OPTICAL, VIBRATIONAL PROPERTIES AND PHOTOCATALYTIC ACTIVITY OF CDO NANOSTRUCTURE
(Elsevier, 2022-11-15) Prakash T; Priyanka R; Siranjeevi R; Ranjith Kumar E; Arunadevi N; Salman S Alharthi
Microwave irradiation was used to prepare the CdO nanostructure for photocatalytic activity. The X-ray diffraction profile after 600 °C annealing confirms the phase transition from monoclinic Cd(OH2) to CdO cubic structure. The typical crystallite sizes of the prepared and annealed nanoparticles are 34 nm–52 nm. The presence of functional groups in the samples is supported by vibrational studies. The optical band gap of as-prepared and annealed samples was calculated using UV spectra. It was discovered to be 3.06 eV for the as-prepared sample and 2.17 eV for the annealed sample. Photoluminescence measurement was selected to study the optical performance of CdO nanoparticles. They confirm the green emission at 522 nm. The morphological and elemental analyses of the CdO nanostructure were recorded using scanning electron microscopy and transmission electron microscopy. The spherical-shaped CdO nanostructures with a uniform size distribution are clearly visible in scanning electron micrographs. TEM micrographs confirm the size of the spherical shaped particles is 50 nm. Using the energy dispersive spectrum, the expected percentages of elements Cd and O were determined. The photocatalytic activity of CdO nanoparticles was tested using methylene blue and rhodamine B.
EVALUATION OF MICROSTRUCTURAL, OPTICAL, VIBRATIONAL PROPERTIES AND PHOTOCATALYTIC ACTIVITY OF CDO NANOSTRUCTURE
(Elsevier, 2022-11-15) Prakash T; Priyanka R; Siranjeevi R; Ranjith Kumar E; Arunadevi N; Salman S, Alharthi
Microwave irradiation was used to prepare the CdO nanostructure for photocatalytic activity. The X-ray diffraction profile after 600 °C annealing confirms the phase transition from monoclinic Cd(OH2) to CdO cubic structure. The typical crystallite sizes of the prepared and annealed nanoparticles are 34 nm–52 nm. The presence of functional groups in the samples is supported by vibrational studies. The optical band gap of as-prepared and annealed samples was calculated using UV spectra. It was discovered to be 3.06 eV for the as-prepared sample and 2.17 eV for the annealed sample. Photoluminescence measurement was selected to study the optical performance of CdO nanoparticles. They confirm the green emission at 522 nm. The morphological and elemental analyses of the CdO nanostructure were recorded using scanning electron microscopy and transmission electron microscopy. The spherical-shaped CdO nanostructures with a uniform size distribution are clearly visible in scanning electron micrographs. TEM micrographs confirm the size of the spherical shaped particles is 50 nm. Using the energy dispersive spectrum, the expected percentages of elements Cd and O were determined. The photocatalytic activity of CdO nanoparticles was tested using methylene blue and rhodamine B.
GROWTH, STRUCTURAL, DIELECTRIC AND OPTICAL CHARACTERISTICS OF GLYCINE PHOSPHITE SINGLE CRYSTALS
(ScienceDirect, 2020) Shanmuga Sundari S; Kanchana P; Arunadevi N; Shobana C
Interesting compounds are formed when glycine reacts with inorganic materials. These compounds exhibit phase transitions with exciting dielectric and elastic properties. In this aspect, glycine with orthophosphorus acid forms glycine phosphite (GPI) single crystals. Good quality, optical transparent glycine phosphite (GPI) single crystals are grown from aqueous solution. GPI crystals have a wide range of nonlinear optical applications. The present work focuses on the growth of GPI from its aqueous solution by slow evaporation method. The PXRD (powder XRD) pattern recorded at ambient temperature shows the single phase nature of the grown GPI crystals and it exists in the monoclinic system with space group P21/a. Etching studies were carried out to know more about the growth morphology and FTIR spectra shows the presence of a variety of normal mode vibration of GPI crystals. Dielectric studies were carried out from 100 K to 383 K. the ferroelectric to para electric transition was observed at 201 K. The dielectric relaxation of the grown crystals was studied using Debye fitting. The activation energy associated with the transition was also calculated. As the GPI crystals are paraelectric at room temperature, no second order non linearity was observed.
HYDRAZINE COMPLEXES OF METAL HYDROXY NAPHTHOATES NEW PRECURSORS FOR METAL OXIDES
(Fast track publication, 2017-06-30) Arunadevi N; Kanchana P
Reaction of hydrazine and 3-hydroxy-2-naphthoic acid with some transition metal ions forms complexes of the type[M(N2H4)2{C10H6(3-O)(2-COO)}]where M = Cd, Zn, Cu and Mn in alcoholic medium.Analytical data confirms the compositions of the complexes. The acid shows dianionic nature in these complexes. IR data indicates the nature of hydrazine in the complexes. Simultaneous TG-DTA studies shows thermal degradation patterns for the complexes. All the complexes follows uniform degradation pattern with the respective metal hydroxy naphthoate as intermediates. The final productsis found to be metal oxides of nano size. The surface morphology and quantative analysis of metal oxides were determined by using SEM analysis. The shape of the nano zinc oxide is rock like hexagonal structure while that of nano Mn oxide is rod like structure which was confirmed by Transmission Electron microscopy analysis.
HYDRAZINIUM METAL 1-HYDROXY-2-NAPHTHOATES NEW PRECURSORS FOR METAL OXIDES
(Indian Journal of Engineering Science and Technology, 2009-01-12) Arunadevi N; Devipriya S; Vairam S
Aromatic metal carboxylates are now-a-days used as precursors for the preparation of metal oxides. In this work, we have presented the formation of metal oxides of nano size by the thermal decomposition of the complexes of 1- hydroxy -2-naphthoates of divalent transition metals, Ni, Co, Cd, Zn and Cu with hydrazinium cation, prepared as crystalline compounds with the general formula,(N2H5)2[M{C10H6(O)(COO)}2.(H2O)2 and characterized by spectroscopic techniques (electronic & IR Spectra, powder XRD method, magnetic moment measurements and thermal analytical (TG-DTA)). The reaction of the acid and hydrazine gives crystalline monohydrazinium salt with formula (N2H5)(C10H6(O)(COO).3H2O. The study of thermal degradation of the complexes indicate that they undergo dehydration in the range of 120-200°C and an oxidative decomposition in the range of 261-700°C showing strong exothermic peaks at 315-493°C resulting in the formation of metal oxides as decomposition residues. The metal oxides obtained by the incineration of these precursors in the muffle furnace at their decomposition temperatures, followed by sintering the metal oxides at the same temperature for about 30 minutes, were found to have the particle size in the range of 17-25 nm.
INFLUENCE OF CARBOXYLIC ACIDS ON STRUCTURAL, OPTICAL, THERMAL, AND ELECTRICAL PROPERTIES OF FERROELECTRIC GLYCINE PHOSPHITE SINGLE CRYSTALS
(SpringerLink, 2022-06-28) Shanmuga Sundari S; Arunadevi N; Kanchana P; Meena P; E, Ranjith Kumar E; Hosam O, Elansary; Eman A, Mahmoud; Shaimaa A M, Abdelmohsen
Glycine phosphite (GPI), a semi-organic nonlinear optical NLO material, has been synthesized at room temperature. Slow evaporation method has been adopted to grow the single crystals of GPI and acetic acid, benzoic acid, formic acid, oxalic acid, and succinic acid-doped GPI crystals. The synthesized crystals are exposed to x-ray diffraction XRD, Fourier transform infrared (FTIR), and differential scanning calorimetry analysis DSC. The effects of doping on the structural parameters are analyzed. All the functional groups are identified by the corresponding peaks in the FTIR spectra. The UV–Vis spectrum shows that the materials have good optical transparency. The energy band gap values are found to be in the range of 5.1–5.4 eV for all the crystals. The mechanical stability of the grown crystals changes with different doping acids. The thermal studies were also affected by the addition of doping acids to the GPI crystal. Growth patterns and defect formation were studied by means of chemical etching. The dielectric constant and loss were evaluated from 300 to 410 K. It confirms that the dielectric constant value of GPI is higher than the acid-doped crystals.
INVESTIGATION ON GROWTH, STRUCTURE, AND PHYSICAL PROPERTIES OF AN ORGANIC CRYSTAL 2-AMINOPYRIDINIUM CYANOACETATE
(Elsevier, 2023-10-05) Sivapriya S; Subramaniyan Raja R; Arun Kumar A; Suryakanth J; Arunadevi N; Ranjith Kumar E; Balasubramanian K
The single crystal of 2-Aminopyridinium cyanoacetate (2APC) has been grown by solution growth slow evaporation technique. Single crystal XRD shows that the grown 2APC is monoclinic crystal system with centrosymmetric space group P21/c and the lattice parameters were found to be a = 9.8955(9) Å b = 6.1096(5) Å c = 14.6132(12) Å. The functional groups and chemical composition of grown 2APC crystal was confirmed by FTIR analysis. UV–Vis spectral study showed that grown crystal has high transparency in the entire visible region and the cut off wavelength at 369 nm. Thermal properties of the crystal were investigated by TGA/DTA analysis. Microhardness mechanical studies show that the hardness number (Hv) of a 2APC single crystal increases with the load as measured by the Vickers microhardness method. The dielectric properties of the grown crystal were analyzed by varying the frequency. The LDT and Z-Scan study were carried out to explore the laser stability and the existence of NLO property in the 2APC.
LEMON JUICE (NATURAL FUEL) ASSISTED SYNTHESIS OF MGO NANORODS FOR LPG GAS SENSOR APPLICATIONS
(Elsevier, 2021-02) Vandamar Poonguzhali R; Ranjith Kumar E; Pushpagiri T; Ananth, Steephen; Arunadevi N; Baskoutas S
Lemon juice assisted combustion method was adopted to prepare MgO nanorods. The role of heat treatment on structural, morphological and gas sensing properties of MgO NPs has been analyzed. The phase analyses of the samples were analyzed using X-ray Diffraction (XRD). The single-phase nanostructure of MgO nanoparticles has been identified from the XRD spectra. The average crystallite sizes are found to be in the range 7.8 nm–19.2 nm. The nanorod like structure of MgO has been recorded through SEM and TEM. The size of MgO nanostructure recorded from TEM is well matched with the crystallite size calculated by XRD. The lemon assisted synthesis of MgO nanoparticles show noticeable gas sensing properties for various gases. In different aspects, gas sensing response of MgO nanoparticles have been analyzed for different gases. The maximum sensing response ~70% has been recorded for LPG at the optimum temperature (OT) 300 °C with the gas concentrations 1000 ppm.
METAL NANOCOMPOSITES FOR ADVANCED FUTURISTIC BIOSENSING APPLICATIONS
(Elsevier, 2022-02-15) Arunadevi N
Nano biosensors is a device with excellent sensing property having dimension in the range of 100 nm. Biosensors will recognize the biological molecules and have heterogeneous type of reaction with analyte. Biosensors are indispensable in medical field for metabolite measurement, monitoring diabetes and biomolecules due to its reproducibility and stability. Metal nanocomposite as biosensors have proven attention to biotechnologist due to its attractive properties. The properties include large surface area which will enhance immobilization of bio recognizers and receptor molecule, improved electro chemical properties and good biocompatibility. This review article covers the classification, characteristics and current development of biosensors with different nano composite materials.
METAL OXIDES: ADVANCED INORGANIC MATERIALS
(Elsevier, 2022-01-14) Arunadevi N; Jone Kirubavathy S
Metal oxides are significant materials in recent research scenario in pharmaceutical applications like anti-oxidant, anti-fungal, antimicrobial, etc., photovoltaic applications with higher efficiency, thin film material, biomedical implant materials, bio-imaging and drug delivery applications, dietary supplements, biosensing platforms, electrodes in various electrochemical cells, photocatalyst, corrosion materials and so on. The present review includes the applications of metal oxides and its composite materials in various fields, their significance in corrosion and electrochemical studies, and their mechanisms. It also highlights its biomedical importance and as sensors which are useful in creating an ecofriendly platform.
NATURAL CITRIC ACID (LEMON JUICE) ASSISTED SYNTHESIS OF ZNO NANOSTRUCTURES: EVALUATION OF PHASE COMPOSITION, MORPHOLOGY, OPTICAL AND THERMAL PROPERTIES
(Elsevier, 2021-08-15) Vandamar Poonguzhali R; Ranjith Kumar E; Sumithra M.G; Arunadevi N; Sharmila Rahale C; Alaa M, Munshi; Gaber A M, Mersal; Nashwa M, El-Metwaly
In recent years, because of their excellent electrocatalytic action and applications in different fields, metal oxide nanostructures have received massive consideration from scientists. Zinc oxide nanostructures are useful materials for a range of sensing applications and possess admirable electrocatalytic properties and stability. The current research presents the natural citric acid assisted synthesis of ZnO nanostructures and their structural, optical, morphological and thermal properties. X-ray diffraction was studied for the phase assessment of as prepared (Z1) and annealed ZnO (Z2) nanostructures and the crystallite sizes of the Z1 and Z2 samples were also located in the range between 35 nm and 38 nm. FESEM and TEM experiments were carried out to explore the surface features of Z1 and Z2 samples. The polycrystalline existence of the samples is demonstrated by the hexagonal, cubic and spherical shaped ZnO nanostructures. The energy band gap of Z1 and Z2 samples was determined (3.16 eV for Z1 and 3.12 eV for Z2) from the UV spectrum. The impact of annealing treatment on the thermal stability of ZnO nanostructures was studied and the main peak was observed for the Z1 sample at ~249 °C and for the Z2 sample at ~289 °C.
NATURAL CITRIC ACID ASSISTED SYNTHESIS OF CUO NANOPARTICLES: EVALUATION OF STRUCTURAL, OPTICAL, MORPHOLOGICAL PROPERTIES AND COLLOIDAL STABILITY FOR GAS SENSOR APPLICATIONS
(Elsevier, 2022-09-15) Vandamar Poonguzhali R; Ranjith Kumar E; Arunadevi N; Ch, Srinivas; Mohamed E, Khalifa; Sraa, Abu-Melha; Nashwa M, El-Metwaly
In the present research, natural ingredient lemon juice was selected as a fuel to prepare nanoparticles under combustion method. The structural properties of nanophase copper oxide nanoparticles (CuO NPs) synthesized by a natural citric acid aided combustion process were studied using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). According to the SEM and TEM images, the manufactured product is made up of spherical nanoparticles with a limited size distribution. According to the XRD pattern, the average crystallite size of monoclinic structured CuO nanoparticles was 10.4 nm for as-prepared samples and 20.5 nm for annealed samples. The zeta potential value confirms the negative surface charge of the samples and the values show the excellent stability (-58.1 mV) for as-prepared sample and the good particles stability (-38.3 mV) was exhibited for heat treated sample. The optical band gap of CuO nanoparticles is 2.01 eV and it decreases to 1.28 eV under heat treatment. The sensitivity and selectivity of the samples were tested under different operating temperatures (OT) and different gas concentrations (GC). Recovery-response time plots confirm that the CuO nanoparticles are promising materials for gas sensor fabrications
NATURAL LEMON EXTRACT ASSISTED GREEN SYNTHESIS OF SPINEL CO3O4 NANOPARTICLES FOR LPG GAS SENSOR APPLICATION
(2023-02-15) Vandamar Poonguzhali R; Ranjith Kumar E; Ch., Srinivas; Mubark, Alshareef; Meshari, M. Aljohani; Ali, A. Keshk; Nashwa, M. El-Metwaly; Arunadevi N
A fresh lemon juice-assisted auto-combustion method was implemented for the synthesis of Co3O4 nanoparticles (Co3O4 NPs). The structural, vibrational, optical, and morphological properties of prepared Co3O4 NPs were investigated at 350 °C. The effects of lemon juice and heat treatment on the physicochemical properties of Co3O4 nanoparticles were investigated. XRD was used to investigate the structure, lattice constant, and crystallite size of Co3O4 NPs. Heat treatment at 350 °C causes the crystallite size to increase from 14.4 nm to 23.7 nm. FT-IR spectroscopy was used to investigate the functional groups and vibrational modes of unheated and heated Co3O4 NPs. Unheated and heated Co3O4 NPs had energy band gaps of 3.14 eV and 3.4 eV, respectively. TEM micrographs of heat-treated Co3O4 NPs confirm the nanoscale range of the particles, which agrees well with the crystallite size determined by XRD. The colloidal stability of Co3O4 NPs has been analyzed through zeta potential values, and the obtained values confirm that the colloidal stability of Co3O4 NPs was influenced by heat treatment. LPG based sensor behavior of Co3O4 nanoparticles has been tested with various aspects of sensing parameters. The result shows that the prepared nanoparticles can be a promising sensing material for toxic gases like LPG, CO2 and NH3.