Indian Journal of Chemistry

Sect. A: Inorganic, Bio-inorganic, Physical, Theoretical & Analytical

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CODEN: ICACEC; ISSN: 0376-4710 (Print), 0975-0975 (Online)

 

 

VOLUME 57A

NUMBER 8-9

AUG-SEPT 2018

CONTENTS

1079

Editorial

 

 

 

1081

 

Crystal engineering of molecular to nonmolecular metal malonates in presence of piperazine: Role of metal ions in tuning architectures

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Kaustubh R Mote, Jency Thomas* &
Arunachalam Ramanan
*

 

 

 

Five transition metal malonate based solids are crystallized in the presence of piperazine. Reaction under ambient condition favors the
growth of [{M(mal)2(H2O)2}{H2pip}] (M: Ni, 1; M: Co, 2), [{Cu(mal)2(H2O)2}{H2pip}].2H2O (3) and [Zn(mal)(pip)(H2O)] (4). While 1-3 are molecular solids, 4 is a 2-D coordination polymer.
Higher acidic condition favors the formation of a molecular organic-inorganic salt, [(H2pip){CoCl4}] (5), while the same reaction under a lesser polar solvent and slightly higher temperature yields a
2-D coordination polymer [{Co(mal)(H2O)(Hpip)}]Cl (6).
The nature of the metal ions and solvent seem to influence the architecture of the solids (molecular or nonmolecular).

 

Graphical abstract.tif

 

 

1091

 

Catechin mediated one-step fabrication of ZnO microspheres: Synthesis, characterization and applications

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Somnath Das & Amitava Pramanik*

 

 

 

Synthesis of hollow ZnO microspheres by a one-step template-free hydrothermal process using (+)catechin as a crystal habit modifier is reported. The ZnO particles show transformation from hexagonal rods to microspheres with increase in concentration of catechin. The microspheres are formed by the aggregation of fine grained  nanosized ZnO particle, and act as an efficient photocatalyst and drug carrier for controlled release of ampicillin.

 

 

 

1100

 

Electrochemical impedance spectroscopy study of
oxygen evolution reaction on nanosized CoWO4
and NiWO4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

V K V P Srirapu, Ajay Kumar, Nirmala Kumari
& Ravindra Nath Singh
*

 

 

 

CoWO4 and NiWO4 are investigated as electrocatalysts for the oxygen evolution reaction in 1 M KOH by electrochemical impedance spectroscopy. The electrode kinetic parameters, Tafel slope and reaction order for the OER determined from the EIS study are very close to those obtained from the steady-state
dc polarization techniques.

 

5.tif

 

 

1106

 

Epoxidation of styrene over MgO-rice derived carbon composite catalyst prepared by in situ transformation technique

 

 

 

 

 

 

 

 

 

 

 

M Kalpana, E Siva Sankar*, K Saidulu Reddy,
K S Rama Rao, J Swathi, V Vijay Kumar,
G Naresh & A Venugopal
*

 

 

 

A low-cost and eco-friendly MgO-rice derived carbon composite catalyst, prepared via in situ transformation technique, is reported for epoxidation of styrene with 84% conversion, and 82% selectivity to styrene epoxide. The catalytic activity is attributed to the presence of well dispersed accessible basic sites obtained through in situ dispersion of MgO over the rice derived carbon.

 

 

 

 

1112

 

Synthesis and characterization of stable ZnO nanoparticles using imidazolium-based ionic liquids and their applications in esterification reaction

 

 

 

 

 

 

 

 

 

 

 

 

S H Kavya, V Vijaya Kumar & C Ramesh Kumar*

 

 

 

ZnO nanoparticles synthesized using microwave conversion method with [OMIM][PF6] ionic liquid as capping agent as well as solvent, are used as a solid reusable acid catalyst for esterification of carboxylic acids with alcohols. The yield with primary alcohols is almost 80%. The acid catalyst exhibits reusability up to four cycles without significant loss of activity.

 

 

 

1121

 

Dicyanomethylene substituted oxocarbon dianions:
A comparative computational study

 

 

 

 

 

 

 

 

 

 

 

 

Promila, Anuj Tripathi & Chetti Prabhakar*

 

 

 

A comparative computational study of various dicyanomethylene substituted dianions of squarate, croconate and rhodizonate with absorption in the visible to the near-infrared region, shows that the absorption energies of the molecules depend largely on the size of the central ring and central angle.

 

GA.tif

 

Notes

 

1128

 

Construction of molecular logic gates through a redox and protonation triggered OFF-ON fluorescent probe

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Qian Li* & Wenjuan Zhu

 

 

 

The redox and protonation triggered OFF-ON fluorescent probe 1 mimics the Boolean logic operation and works as a molecular OR logic gate with protons and oxidants as the stimulus inputs and fluorescent emission at 520 nm as the output. The combination of Cu(ClO4)2 and sodium L-ascorbate produces a molecular system displaying INHIBIT logic due to indirect fluorescence quenching.

 

G A.tif

 

 

1133

 

Synthesis, crystal structure and properties of a
3D zinc(II) coordination polymer with asymmetric
3-amino-1,2,4-triazolate

 

 

 

 

 

 

 

 

 

 

 

 

Wen Tao Fan, Jiao Jiao Du, Quan Qing Xu,
Jun Feng Kou* & Feng Yi Liu
*

 

 

 

A new coordination polymer has been synthesized with zinc
sulfate and an asymmetric 3-substituted triazole ligand at room temperature. Single X-ray analysis displays a six-connected unimodal primitive cubic topological network.

 

1.tif

 

 

1138

 

Synthesis, crystal structure and DFT calculations of copper(I) complex of 2-nitrobenzaldehyde-N1-methyl-thiosemicarbazone

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Dharmender Sharma, Suman Maji, Vivek Gupta & Rekha Sharma*

 

 

 

Stoichiometric complexes of copper(I) halides with 2-nitrobenzaldehyde-N1-methyl thiosemicarbazone and triphenylphosphine, of the type [CuX(h1-S-2-NO2-Hbtsc-N1-Me)(Ph3P)2] (X = I (1), Br (2), Cl (3)), are synthesised. X-ray structure of the copper(I) complex 1 shows distorted tetrahedral geometry around the metal.

 

 

 

1144

 

Thermophysical properties of binary mixtures of polyethylene glycol 400 with n-propanol

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

M M Budeanu* & V Dumitrescu

 

 

 

Densities, viscosities and refractive indices of binary mixture of PEG 400 with n-propanol are reported over the entire composition range at 293.15–303.15 K. Negative deviations are observed for excess molar volumes, deviation in viscosities and excess internal pressures, while positive deviations were observed for refractive indices and excess Gibbs energies of activation of viscous flow.

 

 

 

1151

 

Role of polyvinyl pyrrolidone as a capping agent in the synthesis of magnetite (Fe3O4) nanoparticles

 

 

 

 

 

 

 

 

 

 

 

Sujata Kumari, Neha Yadav, Debasree Ghosh, Chandra Mohan Srivastava* & Sudip Majumder*

 

 

 

Uncapped magnetite (Fe3O4) and magnetite capped with polyvinyl pyrrolidone (Fe3O4-PVP) are synthesized by an aqueous precipitation method. Results suggest that PVP as capping agent reduces grain size, regularizes the shape and increases the crystallinity of Fe3O4 NPs. Fe3O4-PVP NPs show significantly higher thermal stability and surface charge than the uncapped Fe3O4 nanoparticles. Superparamagnetic behavior is shown by both Fe3O4 and Fe3O4-PVP nanoparticles.

 

 

1157

Guide to Authors

 

 

 

Authors for correspondence are indicated by (*)

From the Editor…….

 

My association with the Indian J Chem, Sec A began nearly 30 years ago as a junior member of the editorial team. The journey to becoming Editor has been challenging and deeply fulfilling.
For almost 10 years, I have had the privilege to serve as the Editor of the Indian J Chem, Sec A.
The Aug-Sept 2018 issue is the last one under my editorship.

During the past 10 years, IJCA published several thematic issues on contemporary themes and thrust areas, which were highly acclaimed by the readers. These include issues on Ionic Liquids, Bioinorganic Chemistry, Carbon Dioxide Sequestration, Complex Chemical Systems, Catalysis, and, Chemical Reactivity Theory. Each of these issues was guest-edited by eminent researchers and their enthusiasm was very encouraging and invigorating. Of special mention is the Anniversary Issue in January 2012, to mark the 50th year of publication of journal. This issue, titled “Perspectives & Challenges”, is a valuable collection of invited articles by distinguished Indian chemists on some of the recent major developments in inorganic and physical chemistry.

This period saw the journal hosted on the NISCAIR Online Periodicals Repository (NOPR), giving free access to the full text of its articles. This has increased the visibility of the journal manifold. The recently started service to host electronic supplementary data of IJCA papers on the
NISCAIR open access repository is commensurate with the practices followed by well known international journals. Submission and review process of articles through the journal’s
Online Submission Portal was started a couple of years ago. For the most part, this has reduced processing time considerably.

I take this opportunity to thank the Editorial Board Members, past and present, for their wholehearted support and guidance. My special thanks to our reviewers for their painstaking efforts in helping us to maintain the quality of the journal. I am also thankful to the authors and readers of IJCA for reposing faith in our ability to communicate their research results effectively.

I am grateful for the opportunity to have been at the helm of this prestigious and respected journal. I am confident that with the continuing support of everyone, the Indian J Chem, Sec A shall reach new heights.

 

 

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August 2018

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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Indian Journal of Chemistry

Vol. 57A, Aug-Sept 2018, pp. 1081-1090

 

Crystal engineering of molecular to nonmolecular metal malonates in presence of piperazine: Role of metal ions in tuning architectures

Kaustubh R Mote, Jency Thomas, * & Arunachalam Ramanan*

Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110 016, India

Email: aramanan@chemistry.iitd.ac.in (AR)/ jencythomas@stthomas.ac.in (JT)

Received 2 May 2018; revised and accepted 19 July 2018

Growth of transition metal malonate (mal) based solids from aqueous solution is investigated in the presence of piperazine (pip). Reaction under ambient conditions favored the growth of [{M(mal)2(H2O)2}{H2pip}] (M: Ni, 1; M: Co, 2), [{Cu(mal)2(H2O)2}{H2pip}].2H2O (3), and, [Zn(mal)(pip)(H2O)] (4). While 1-3 are molecular solids, 4 is a 2-D coordination polymer. In the case of cobalt, higher acidic condition favored the formation of a molecular organic-inorganic salt, [(H2pip){CoCl4}] (5). The same reaction under a different crystallization condition, i.e., lesser polar solvent and slightly higher temperature (solvothermal) led to a 2-D coordination polymer [{Co(mal)(H2O)(Hpip)}]Cl (6). A retrosynthesis approach has been employed to interpret the crystallization reaction and compare the supramolecular reactivity of aggregating metal tectons in engineering the molecules to form either a molecular solid or coordination polymer.

Keywords: Crystallization, Transition metal ions, Malonate, Piperazine, Nickel, Cobalt, Copper, Zinc

 

Indian Journal of Chemistry

Vol. 57A, Aug-Sept 2018, pp. 1091-1099

 

Deviations in viscosity and thermodynamics of viscous flow for binary mixtures of methyl acrylate with 1-alkanols at different temperatures

A K Nain*, P Droliya & J Gupta

Department of Chemistry, Dyal Singh College (University of Delhi), New Delhi 110 003, India

Email: ak_nain@yahoo.co.in

Received 7 November 2017; revised and accepted 14 May 2018

The viscosities (h) of binary mixtures of methyl acrylate with 1-butanol, 1-hexanol, 1-octanol and 1-decanol, including those of pure liquids, over the entire composition range are reported at different
temperatures (288.15, 293.15, 298.15, 303.15, 308.15, 313.15, and 318.15) K. From the experimental data,
the deviations in viscosity (
Dh) have been calculated. The Dh values are found to be negative over
the entire composition range for these mixtures, indicating the presence of weak interactions between methyl acrylate and 1-alkanol molecules. The magnitude of negative deviations in
Dh values follows the
order: 1-butanol < 1-hexanol < 1-octanol < 1-decanol. It is observed that
Dh values depend upon the length of the alkyl chain in 1-alkanols. Also, the interactions between methyl acrylate and 1-alkanols decrease with increase in alkyl chain length. The thermodynamics of viscous flow has been analyzed by using Eyring and Arrhenius approaches and the results have been compared and discussed in terms of intermolecular interactions between the molecules. Further, the viscosities of these binary mixtures computed theoretically by using various empirical and semi-empirical models correlated well with the experimental findings in terms of average standard deviations.

Keywords: Solution chemistry, Binary mixtures, Viscosity, Methyl acrylate, Alkanols, Molecular interactions, Thermodynamics of viscous flow

 

Indian Journal of Chemistry

Vol. 57A, Aug-Sept 2018, pp. 1100-1105

 

Electrochemical impedance spectroscopy study of the oxygen evolution reaction on nanosized CoWO4 and NiWO4

V K V P Srirapu, Ajay Kumar, Nirmala Kumari & Ravindra Nath Singh*

Department of Chemistry, Centre of Advanced Study, Institute of Science, Banaras Hindu University, Varanasi 221 005, India

Email: rnsbhu@rediffmail.com

Received 1 May 2018; revised and accepted 23 July 2018

CoWO4 and NiWO4 have been prepared by a co-precipitation method and investigated as electrocatalysts for the oxygen evolution reaction in 1 M KOH by electrochemical impedance spectroscopy. The electrode kinetic parameters such as the electrochemical active surface area, exchange current density, Tafel slope, and the reaction order are determined. Results have shown that the values of the Tafel slope and reaction order obtained from the EIS study excellently match with those determined by dc techniques.

Keywords: Electrochemistry, Electrochemical impedance, Oxygen evolution, Electrode kinetics, Metal tungstates, Tungstates, Cobalt, Nickel

 

Indian Journal of Chemistry

Vol. 57A, Aug-Sept 2018, pp. 1106-1111

 

Epoxidation of styrene over MgO-rice derived carbon composite
catalyst prepared by in-situ transformation technique

M Kalpana, E Siva Sankar*, K Saidulu Reddy, K S Rama Rao, J Swathi, V Vijay Kumar, G Naresh &
A Venugopal*

Catalysis and Fine Chemicals Department, CSIR-Indian Institute of Chemical Technology, Tarnaka,
Hyderabad 500 007, Telangana State, India

Email: sivasankar.enumula@gmail.com (ESS)/ akula@iict.res.in (AV)

Received 23 July 2018; revised and accepted 8 August 2018

With a view to develop eco-friendly and metal-free catalysts, herein we report MgO-rice derived carbon composite for epoxidation of styrene to styrene epoxide. MgO-C catalysts prepared via in situ transformation technique are characterized by powder XRD, BET-surface area, Raman spectroscopy, CO2-TPD, CHNS analysis and TGA techniques. Under optimized reaction conditions, MgO-C0.5 catalyst efficiently catalyzed the reaction with 84% conversion of styrene yielding 82% selectivity to styrene epoxide. The characterization results suggest that the catalytic activity is attributed to the presence
of well dispersed accessible basic sites obtained through in situ dispersion of MgO over rice derived carbon.
MgO-C0.5 catalyst is recyclable up to four cycles without significant loss in the activity and selectivity.

Keywords: Catalysts, Composites, Carbon composites, Epoxidation, Styrene, Styrene epoxide

 

Indian Journal of Chemistry

Vol. 57A, Aug-Sept 2018, pp. 1112-1120

 

Synthesis and characterization of stable ZnO nanoparticles using
imidazolium-based ionic liquids and their applications in
esterification reaction

S H Kavya, V Vijaya Kumar & C Ramesh Kumar*

Organic Chemistry Laboratory, Department of Chemistry, Vel Tech Rangarajan Dr Sagunthala
R&D Institute of Science and Technology,
Avadi, Chennai 600 062, Tamil Nadu, India.

Email: nscrameshkumar@gmail.com

Received 4 September 2017; re-revised and accepted 3 August 2018

ZnO nanoparticles have been synthesized from zinc acetate using 1-octyl-3-methylimidazolium hexafluorophosphate as capping agent under microwave irradiation condition in a very short period of time and characterized using UV-visible spectroscopy, powder X-ray diffraction, scanning electron microscopy, transmission electron microscopy and NH3-TPD analysis. The ZnO NPs have been used as a solid reusable acid catalyst for esterification of carboxylic acids with alcohols.

Keywords: Catalysts, Ionic liquids, Nanoparticles, Solid acid catalysts, capping agents, Esterification, Zinc oxide, Microwave synthesis

 

Indian Journal of Chemistry

Vol. 57A, Aug-Sept 2018, pp. 1121-1127

 

Effect of third component on separation behavior of
water+t-butanol+Na2SO3/Na2SO4 system at 298±2 K

Vidhya V Jadhava, b, Sanjay S Kolekarb, Rajendra R Kumbharc, Bhaskar V Tamhankard, Sandip R Sabalea,*

aDepartment of Chemistry, Jaysingpur College, Jaysingpur 416 101, (Shivaji University), India

Email: srsabale@gmail.com

bDepartment of Chemistry, Shivaji University, Kolhapur 416 004, India

cDepartment of Chemistry, YCIS Satara 415 004, (Shivaji University), India

dDepartment of Chemistry, Wilingdon College, Sangli 416 415 (Shivaji University), India

Received 31 January 2018; revised and accepted 31 May 2018

The liquid-liquid and liquid-liquid-solid equilibria for the ternary t-butanol-water-Na2SO3/Na2SO4 system is reported at ambient pressure and at 298±2 K. The solubility data of solutions of Na2SO3/Na2SO4 in water, t-butanol and solutions of varying compositions of t-butanol in water are reported. The phase diagrams for the studied systems are developed and salting-out effect of salt anion has been described. The structural properties of aqueous t-butanol solutions and the salting-out effect of SO32- and SO42- ions to cause phase separation have been explained. The salting-out ability of Na2SO3 is higher than that of Na2SO4 since the Gibbs free energy of hydration (ΔGhyd) of SO42- (−1080 kJ mol-1) is lower than that of SO32- (−1295 kJ mol-1) ion.

Keywords: Solution chemistry, Phase diagrams, Butanol, Water, Sulphite, Sulphate, Na2SO3, Na2SO4, Salting-out

 

Indian Journal of Chemistry

Vol. 57A, Aug-Sept 2018, pp. 1128-1132

 

Construction of molecular logic gates through a redox and
protonation triggered OFF-ON fluorescent probe

Qian Li* & Wenjuan Zhu

Department of Cultivation and Identification of Chinese Herbal Medicine/ Institute of Traditional Chinese Medicine,
College of Agronomy, Gansu Agricultural University,
Lanzhou 730070,  PR China

Email: liqian1984@gsau.edu.cn

Received 18 March 2018; revised and accepted 20 July 2018

A BODIPY based fluorescent probe 1 for protons and oxidants has been reported. Probe 1 shows weak fluorescence due to the PET process and exhibits OFF-ON fluorescent emission response towards protons (HCl) and oxidants (Cu(ClO4)2) in CH3CN-H2O and CH3CN solution. The suppressed PET process is responsible for the change in fluorescent emission. Further, the OFF-ON fluorescent probe 1 can mimic the Boolean logic operation and work as a molecular OR logic gate with protons and oxidants as stimulus inputs and fluorescent emission at 520 nm as output. The combinations of Cu(ClO4)2 and sodium L-ascorbate can be used to produce a molecular system displaying INHIBIT logic, due to indirect fluorescence quenching.

Keywords: BODIPY, Molecular logic gates, Molecular machines, Switchable materials, Redox fluorescent probes, Fluorescent probes, OFF-ON probes, Protonation

 

Indian Journal of Chemistry

Vol. 57A, Aug-Sept 2018, pp. 1133-1137

 

Synthesis, crystal structure and properties of a 3D zinc(II) coordination polymer with asymmetric 3-amino-1,2,4-triazolate

Wen Tao Fan, Jiao Jiao Du, Quan Qing Xu, Jun Feng Kou* & Feng Yi Liu*

College of Chemistry and Chemical Engineering Yunnan Normal University, Kunming, Yunnnan, 650 500, PR China

Email: kjf416@163.com (JFK)/ lfy20110407@163.com (FYL)

Received 4 May 2018; revised and accepted 27 July 2018

A new coordination polymer, [Zn2SO4(atz)2(H2O)2]·(H2O)4 (1) (Hatz = 1H-3-amino-1,2,4-triazole) has been synthesized using zinc sulfate and an asymmetric 3-substituted triazole ligand at room temperature. X-ray analysis reveals that complex 1 shows a 3D-framework containing Zn2(atz)2(H2O)2SO4 subunits, which display a 6-coordinated unimodal pcu topological network. Further, complex 1 exhibits purple fluorescence with an emission maximum at 405 nm in the solid state at room temperature.

Keywords: Coordination polymers, 3D-Framework, X-ray structure, Fluorescence, Zinc sulfate, Triazoles,
Symmetric triazoles

 

Indian Journal of Chemistry

Vol. 57A, Aug-Sept 2018, pp. 1138-1143

 

Synthesis, crystal structure and DFT calculations of copper(I) complex of 2-nitrobenzaldehyde-N1-methylthiosemicarbazone

Dharmender Sharmaa, Suman Majia, Vivek Guptab & Rekha Sharmaa, *

aDepartment of Chemistry, Lovely Professional University, Phagwara, Punjab, India

Email: rekha.pardeep78@gmail.com

bPost Graduate Department of Physics & Electronics,
University of Jammu, Jammu Tawi 180 006, India

Received 24 March 2017; re-revised and accepted 27 July 2018

Copper(I) halides (I, Br, Cl) reacted with 2-nitrobenzaldehyde-N1-methylthiosemicarbazone (L = 2-NO2-Hbtsc-N1-Me) and triphenylphosphine in 1:1:2 (M:L:Ph3P) molar ratio to form stoichiometric complexes, [CuX(h1-S-2-NO2-Hbtsc-N1-Me)(Ph3P)2] (X  = I (1), Br (2), Cl (3)). Formation of these complexes has been confirmed by elemental analysis, IR and 1H NMR. The X-ray structure of complex 1, showed the presence of two molecules with slightly different bond parameters. Geometry around copper(I) center is distorted tetrahedral. Two molecules are interconnected by H-bonding between imino nitrogen N(14) of one molecule and phenyl hydrogen of one of the triphenylphospine molecules of the second molecule, {H(14)N×××HC, 2.701 Ĺ, N×××H-C, 156.85°) forming a H-bonded dimer. The geometry of the thione ligated copper(I) complex was optimized in gas phase by employing B3LYP/6-31G(d, p) method using Gaussian 09 software package. The optimized geometry of the copper(I) complex displays similar structure as that of the crystal structure of complex 1.

Keywords: Coordination chemistry, Crystal structures, Thiosemicarbazones, Copper, Triphenylphosphine, Tetrahedral monomers

 

Indian Journal of Chemistry

Vol. 57A, Aug-Sept 2018, pp. 1144-1150

 

Thermophysical properties of binary mixtures of polyethylene glycol 400 with n-propanol

M M Budeanu* & V Dumitrescu

Chemistry Department, Petroleum and Gas University of Ploiesti, Blv. Bucharest, No. 39, Ploiesti, Romania

Email: m19magda@yahoo.com

Received 23 April 2018; revised and accepted 30 July 2018

Densities (ρ), viscosities (η) and refractive indices (nD) of the binary system polyethylene glycol 400+n-propanol have been measured at (293.15, 298.15 and 303.15) K and at atmospheric pressure, over the entire composition range. From experimental results, the values of excess properties have been calculated and fitted to the Redlich-Kister equation. Negative deviations are observed for excess molar volumes, deviation in viscosities and excess internal pressures, while positive deviations are observed in the case of refractive indices and excess Gibbs energies of activation of viscous flow at all of the temperatures and in the entire concentration range. Of the studied models, the Jouyban-Acree model is suitable for describing the viscosity of the PEG 400+n-propanol binary system. The refractive index predicted by the Newton-mixing rule shows the best agreement with experimental values. The values of thermodynamic functions of activation viz., DG#, DH# and DS#, are positive for the PEG 400+n-propanol binary system.

Keywords: Solution chemistry, Polyethylene glycol, n-Propanol, Thermophysical properties, Excess properties, Binary systems, Density, Refractive indices

 

Indian Journal of Chemistry

Vol. 57A, Aug-Sept 2018, pp. 1151-1155

 

Role of polyvinyl pyrrolidone as a capping agent in the synthesis of magnetite (Fe3O4) nanoparticles

Sujata Kumaria, Neha Yadava, Debasree Ghosha, Chandra Mohan Srivastavaa, * & Sudip Majumdera, b, *

aDepartment of Chemistry, Amity School of Applied Science, Amity University Haryana

bCentre for Nanoscience and Technology, Amity University Gurgaon (Manesar) 122 413, Haryana, India

Email: smsmajumder@ggn.amity.edu (SN)/ cmsrivastava@ggn.amity.edu (CMS)

Received 7 June 2018; revised and accepted 2 August 2018

Uncapped magnetite (Fe3O4) and magnetite capped with polyvinyl pyrrolidone (PVP) (Fe3O4-PVP) have been synthesized by a rapid, cost effective aqueous precipitation method. The nanoparticles are characterized by powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and UV spectroscopy. The role of PVP as a capping agent in the synthesis of magnetite nanoparticles has been investigated. Thermal stability and surface charge of the nanoparticles have been characterized by thermogravimetric analysis, differential scanning calorimetry (DSC) and zeta potential measurements. Results suggest that PVP as a capping agent reduces the grain size, regularizes the shape, and increases the crystallinity of Fe3O4 nanoparticles. Thermal stability and surface charge of Fe3O4-PVP nanoparticles are also significantly higher as compared to the uncapped Fe3O4 nanoparticles. Magnetic characterization by vibrating sample magnetometry of both Fe3O4 and Fe3O4-PVP nanoparticles indicates the superparamagnetic behavior of the nanoparticles.

Keywords: Nanoparticles, Magnetite nanoparticles, Ferrites, Superparamagnetism, Co-precipitation, Iron oxide, Polyvinyl pyrrolidone