BHU Institutional Repository :: Browsing by Author "Chatterjee, B."

Browsing by Author "Chatterjee, B."

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Characterization and electrical properties of polyvinyl alcohol based polymer electrolyte films doped with ammonium thiocyanate
(Elsevier Ltd, 2014) Kulshrestha, N.; Chatterjee, B.; Gupta, P.N.
In this communication, films of polyvinyl alcohol (PVA) polymer complexed with ammonium thiocyanate (NH4SCN) salt were studied. XRD (X-ray diffraction) was used to study the complexation of salt with the polymer matrix and amorphicity in the films. DSC (differential scanning calorimetry) studies showed that the glass transition temperatures (Tg) of the PVA:NH 4SCN complexed films were less than pristine PVA. Raman analysis was analyzed in order to study the change in the vibrational bands due to the complexation of salt with PVA. Optical micrographs confirm the fractal formation in 75:25 and 70:30 PVA:NH4SCN films. Ionic transference number was estimated by Wagner's polarization method and its large value indicates that conduction takes place mainly due to mobile ionic species. Maximum conductivity ∼10-3 S/cm at room temperature was obtained for 70:30 ratio of PVA: NH4SCN polymer electrolyte films. © 2014 Elsevier B.V.
Differential organization of a LINE-1 family in Indian pygmy field mice
(2003) Chatterjee, B.; Bahadur, M.; Srivastava, S.; Sharma, T.
Southern blot hybridization analysis of genomic DNAs digested with restriction endonuclease EcoR I and Ava II from Mus musculus domesticus, Mus booduga and Mus terricolor with a cloned repetitive DNA fragment of Mus booduga as a probe showed difference in restriction pattern of this DNA in these three species. Further Southern analysis of the BamH I digested genomic DNAs from these species hybridized with cloned DNA fragment as a probe and sequencing of the cloned DNA revealed that this 252 bp cloned DNA fragment is a part of BamHI repeat element of genus Mus and is 87 % homologous to the contiguous portion of the Mus musculus domesticus LINE-1 element. The species specific fragment pattern generated by different restriction endonucleases using this DNA as a probe revealed difference in the organization of LINE-1 repetitive element in the three species of genus Mus.
Effect of Sr-doping on multiferroic properties of Bi 0.8La 0.2Fe 0.9Mn 0.1O 3
(2012) Ghosh, Anup K.; Kevin, H.; Chatterjee, B.; Dwivedi, G.D.; Barman, A.; Yang, H.D.; Chatterjee, S.
The effect of Sr-doping on ferroelectricity and ferromagnetism at room temperature has been studied for Bi 0.8La 0.2Fe 0.9Mn 0.1O 3 ceramic system. X-ray diffraction shows that a structural phase transition occurs from rhombohedral structure of BiFeO 3 (space group R3c) to orthorhombic structure of Bi 0.8La 0.2FeO 3 (space group C222). Substitutions of Sr-ions in Bi-site and Mn-ions in Fe-site do not induce any further structural change. Moreover, doping of Sr-ions plays a crucial role to obtain single phased samples. DTA and TGA studies show that both the magnetic transition temperature ( TM) and the ferroelectric transition temperature ( TC) decrease for Bi 0.7Sr 0.1La 0.2Fe 0.9Mn 0.1O 3. Sr-doping enhances the ferroelectric property by increasing the electric polarization. MH measurement shows that Sr-ions partially destroy the spin cycloidal structure in it giving rise to weak ferromagnetism (nonlinearity) at room temperature. © 2011 Elsevier Ltd. All rights reserved.
Electrical properties of starch-PVA biodegradable polymer blend
(Institute of Physics Publishing, 2015) Chatterjee, B.; Kulshrestha, N.; Gupta, P.N.
Solid polymer electrolyte films were prepared by adding different contents of potassium chloride (KCl) in a polymer matrix composed of two versatile biodegradable polymers: starch and polyvinyl alcohol (PVA), using the solution cast method. The complexation of the added salt (KCl) with the polymer matrix was confirmed from an x-ray diffraction study (XRD). The evolution of a smooth and uniform morphology with the increasing content of KCl was confirmed from scanning electron microscopy (SEM). The transference number measurement established ions as the dominant charge carriers in the system. The maximum ionic conductivity ∼5.44 × 10-5 S cm-1 at ambient conditions was obtained for the film with 1.5 wt% of KCl using complex impedance spectroscopy. The ionic conductivity and dielectric constant increased with the salt content, thus affirming the amplification in the number of charge carriers. The noteworthy aspect of the investigation is the observation of appreciable ionic conductivity at a relatively low salt content. Low values of activation energy obtained from temperature-dependent ionic conductivity could be favorable from the point of view of the application. Electric modulus studies confirmed the absence of electrode polarization effects in the polymer electrolyte films. The scaling of the electric modulus shows a distribution of relaxation times in the polymer electrolyte films. The study unveils the efficiency of the starch-PVA blend, with glycerol and citric acid as additives, as a hopeful material for preparing biodegradable solid polymer electrolyte films. © 2015 The Royal Swedish Academy of Sciences.
Enhancement of ferromagnetic and ferroelectric properties in codoped biFeO3
(Chemical Publishing Co., 2011) Chatterjee, B.; Kevin, H.; Dwivedi, G.D.; Yang, H.D.; Chatterjee, S.; Ghosh, A.K.
Co-doped insulating Bi0.8La0.2Fe 1-xMnxO3, (x = 0, 0.1) ceramics were prepared by conventional solid state reaction method. The XRD study shows that 20 % substitution of La ions changes the structure from rhombohedral (space group R3c) that of BaFeO3 to the orthorhombic (C222) for Bi0.8La 0.2FeO3 (BLFO). For further substitution of Mn-ions in Fe-site no structural change occurs. From DTA and TGA study, it is observed that magnetic transition temperature (Tm) decreases appreciably whereas ferroelectric transition temperature (TC) does not affect much with the increase of Mn-concentration. The magnetization-magnetic field measurements show that increase of magnetization for co-doping of La and Mn in Bi 0.8FeO3 is due to the destruction of the spin cycloid structure in it and the introduction of the mixed valance state. P-E measurement shows the ferroelectric nature of the sample.
Erratum:Characterization and electrical properties of polyvinyl alcohol based polymer electrolyte films doped with ammonium thiocyanate(Materials Science and Engineering B (2014)184(49-57)DOI: 10.1016/j.mseb.2014.01.012)
(Elsevier Ltd, 2015) Kulshrestha, N.; Chatterjee, B.; Gupta, P.N.
[No abstract available]
Nano composite solid polymer electrolytes based on biodegradable polymers starch and poly vinyl alcohol
(Elsevier B.V., 2016) Chatterjee, B.; Kulshrestha, Niharika; Gupta, P.N.
An attempt has been made to prepare nano composite solid polymer electrolytes by adding nano fumed silica in different weight ratios in a polymer matrix composed of biodegradable polymers Starch and Poly Vinyl Alcohol (PVA) to get high ionic conductivity with good mechanical strength. Fourier Transform InfraRed spectroscopy (FTIR) was used to confirm the complexation and interaction of the nano filler with the polymer matrix. From the FTIR investigations it could be established that the formation of C-O-Si bonds by nano fumed SiO2 with Starch and PVA lead to the crucial structural modification that finally increase the conductivity of the sample. Dielectric and frequency dependent measurements substantiate the sharp increase in number of charge carriers as the major factor contributing to the enhancement of the conductivity for 3 wt% nano fumed silica. Electric modulus studies confirmed the ionic nature and indicate absence of electrode polarization in the system. Maximum ionic conductivity ∼10-3 S/cm could be realized for 3 wt% silica at ambient condition. © 2016 Elsevier Ltd. All rights reserved.
Nanocomposite films dispersed with silica nanoparticles extracted from earthworm humus
(2012) Chatterjee, B.; Gupta, P.N.
Research in the field of polymer electrolytes in recent years has been focused in achieving maximum conductivity at ambient conditions. Addition of ceramic nanoparticles to polymer matrices has been found to be an effective way to realize large ionic conductivity. A cost effective method of extracting silica nanoparticles from earthworm humus has been reported. To prepare polymer electrolyte films of PVA-PVP blend in 50:50 ratio by weight was taken as the polymer matrix and orthophosphoric acid (H 3PO 4) was added to the polymer blend solution. Nanocomposite polymer electrolytes were prepared by adding known amounts of SiO 2 nanoparticles to polymer electrolyte solution. XRD scans of the polymer electrolyte films reveal a well dispersed state of the nanoparticles in the polymer matrix. DSC studies have shown a reduction in Tg of the polymer electrolytes with addition of SiO 2 nanoparticles. The highest conductivity has been found to be 2.4 × 0 - 4 S/cm at 2 wt.% silica doping at room temperature. Transference number measurements have shown that the conductivity of the samples is mainly dominated by the motion of the ions. © 2012 Elsevier B.V.
Role of codoping on multiferroic properties at room temperature in BiFeO3 ceramic
(Elsevier Ltd, 2013) Ghosh, Anup K.; Dwivedi, G.D.; Chatterjee, B.; Rana, B.; Barman, A.; Chatterjee, S.; Yang, H.D.
Role of codoping (20% La in Bi-site and 10% Mn in Fe-site) on mutiferroic properties in insulating BiFeO3 ceramic have been investigated. The X-ray diffraction (XRD) with Rietveld refinement shows that the structure of Bi0.8La0.2FeO3 is orthorhombic (Pnma). Furthermore, it shows that on substitution of 10% Mnions in Fe-site, no structural change occurs which has been supported by micro-Raman study. DTA study shows that ferroelectric transition temperature (TC) decreases very fast due with La-doping and slowly with the Mn-doping. Measurement on magnetization vs. applied magnetic field (M-H) shows increase of magnetization due to codoping of La and Mn in BiFeO 3. This may be due to partly destruction or suppression of the spin cycloid structure in it and/or the introduction of the mixed valance state. P-E measurement shows high leakage in Bi0.8La0.2Fe0.9Mn0.1O3. © 2013 Elsevier Ltd. All rights reserved.
Signature of ferroelectricity in magnetically ordered Mo-doped CoFe 2O4
(2010) Dwivedi, G.D.; Tseng, K.F.; Chan, C.L.; Shahi, P.; Lourembam, J.; Chatterjee, B.; Ghosh, A.K.; Yang, H.D.; Chatterjee, Sandip
Coexistence of both magnetic ordering and ferroelectricity (with giant dielectric constant) have been observed for the first time in Co(Fe 1-xMox)2O4. The magnetization of Co(Fe1-xMox)2O4 ranges from 0 to 0.1) was found to increase with doping concentration of Mo. The magnetic properties indicate that Mo goes into the tetrahedral site. The giant dielectric constant may be attributed to the Maxwell-Wagner relaxation mechanism. © 2010 The American Physical Society.
Simultaneous presence of ferroelectricity and magnetism in Mo-doped CoFe2O4
(2010) Dwivedi, G.D.; Tseng, K.F.; Chan, C.L.; Shahi, P.; Chatterjee, B.; Ghosh, A.K.; Yang, H.D.; Chatterjee, Sandip
Signature of ferroelectricity has been observed for the first time in magnetically ordered Co(Fe1-xMox)2O 4. The structural property of Co(Fe1-xMox) 2O4 (x ranges from 0 to 0.1) indicates that Mo goes into the tetrahedral site. The frequency dependent P-E loop indicates the existence of weak ferroelectricity in Mo-doped CoFe2O4. © 2010 American Institute of Physics.
Structural, thermal, electrical, and dielectric properties of synthesized nanocomposite solid polymer electrolytes
(SAGE Publications Ltd, 2014) Kulshrestha, N.; Chatterjee, B.; Gupta, P.N.
In the present article, polyvinyl alcohol (PVA) polymer, sodium iodide (NaI) salt, and fumed silica nanoparticles nanofiller have been used for the preparation of solid polymer electrolyte films. Fourier transform infrared spectroscopy has been performed to study the vibrational change due to the complexation among polymer, salt, and nanofiller. X-Ray diffraction has been carried out to study the structural changes in the PVA:NaI (60:40) polymer electrolyte films with fumed silica nanoparticles as dopant. Differential scanning calorimetry studies show decreasing trend in the glass transition temperature for nanocomposite polymer electrolyte films. Thermogravimetric analysis has been performed to study the thermal degradation of the sample. Determination of transference number using Wagner's polarization technique indicates that the ions are the dominant mobile species. Maximum conductivity of approximately 3.8 × 10â̂?3 S cmâ̂?1 at room temperature has been estimated for PVA:NaI (60:40) film containing 0.5% fumed silica nanoparticles with low value of activation energy. Dielectric relaxation studies with temperature show shifts of the relaxation time toward higher value for samples of nanocomposite polymer electrolyte films. © The Author(s) 2014.

Browsing by Author "Chatterjee, B."

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