MADHURI WUPPULLURI
@vit.ac.in
Assistant Professor Senior Grade, Centre for Crystal Growth, Department of Physics
VIT Vellore
EDUCATION
PhD in Physics
RESEARCH INTERESTS
Ferrites
ferroelectrics
piezoelectrics
multiferroics
ceramics
ceramic composites
electroceramics
magnetic materials
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Avanish Babu Thirumalasetty, Siva Pamula, Thiyagarajan Krishnan, Vaishnavi Khade, Pathan Sharief, Siva Kumar Kota Venkata, Srinivas Adiraj, and Madhuri Wuppulluri
Springer Science and Business Media LLC
AbstractHigh-performance lead-free Barium Zirconium Titanate (BZT) based ceramics have emerged as a potential candidate for applications in energy storage, catalysis for electro chemical energy conversion and energy harvesting devices as presented in this work. In the present study hybrid microwave sintered BZT are studied for dielectric, ferroelectric and phase transition properties. BZT ceramic exhibits tetragonal structure as confirmed by the Retvield refinement studies. XPS studies confirms the elemental composition of BZT and presence of Zr. Polarization versus electric field hysteresis loops confirms the ferroelectric behaviour of BZT ceramic. Encouragingly, the BZT showed a moderate energy storage efficiency of 30.7 % and relatively good electro chemical energy conversion (HER). Excellent catalytic activity observed for BZT electrode in acid medium with low Tafel slope 77 mV dec-1. Furthermore, electrospun nanofibers made of PVDF-HFP and BZT are used to make flexible piezoelectric nano generators (PENGs). FTIR studies show that the 16 wt% BZT composite ink exhibits a higher electroactive beta phase. The optimized open-circuit voltage and short circuit current of the flexible PENG exhibits 7Vpp and 750 nA under an applied force of 3N. Thus, flexible and self-powered BZT PENGs are alternative source of energy due to its reliability, affordability and environmental-friendly nature.
Anjana Vinod, D. Arvindha Babu, and Madhuri Wuppulluri
American Chemical Society (ACS)
Energy-efficient refrigeration technology needs to advance ineluctably due to rising energy consumption and diminishing fossil fuel and primitive hydrocarbon reserves. Further, the existing gas compression method releases huge amount of chlorofluorocarbons (CFCs) that deplete the ozone layer. This is a global concern, which demands an immediate remedial technology. As a potential solution to the problem of sustainability and a means of meeting the ever-increasing demand for energy, environmentally friendly and socially responsible renewable energy sources could serve as an ideal replacement for traditional refrigeration technology. Solid-state refrigeration using magnetocaloric materials is one prominent technique that can be adopted for clean and economical refrigeration or cooling requirements. In this review, we briefly introduce the present understanding on magnetocaloric LaFe13–xSix alloys with a specific emphasis on their application in magnetic refrigeration. This paper deals with the advantages and disadvantages of different synthesis methods for producing LaFe13–xSix and enhancing its magnetocaloric effects. Annealing time, yield, composition, and relative cooling power are examined as prospective industrial implementation factors for the La(Fe,Si)13 synthesis process. The initial sections have been devoted to an overview of the magnetocaloric effect and its different types and history. Further, the article reviews the evolution of a new preparation method called melt spinning, other synthesizing methods, and some developments around the world for the prototypes of La(Fe,Si)-based magnetic refrigeration methods. According to the findings in the scholarly literature, the synthesis process of melt spinning has the potential to be commercialized because of its capacity to create huge quantities of La(Fe,Si)13 with a high purity in a very short amount of time.
A. Anagha, A. Joshua, Basil Chacko, T. Avanish Babu, Sriram Srigiri, and W. Madhuri
Elsevier BV
Vaishnavi Khade, Avanish Babu Thirumalasetty, Asmita Ajay Rathod, Yogesh Kumar Chaoukiker, and Madhuri Wuppulluri
Royal Society of Chemistry (RSC)
In this article, we compare the EMI shielding performance of rigid and flexible composites of cobalt nickel ferrite.
Chinmay Chandan Parhi, Avanish Babu Thirumalasetty, Ajit Raymond James, Yogesh Kumar Choukiker, and Madhuri Wuppulluri
Royal Society of Chemistry (RSC)
A new composite with two-dimensional graphene oxide decoration is designed through microwave sintering for efficient microwave attenuation.
Chinmay Chandan Parhi, Avanish Babu Thirumalasetty, Ajit Raymond James, and Madhuri Wuppulluri
American Chemical Society (ACS)
The escalating demand for energy-related devices has prompted an intensive study on materials for energy harvesting and storage. Recently, due to the toxicity of lead-based materials, researchers have drawn their attention to lead-free ferroelectrics. However, it is indisputable that commercially lead zirconium titanate (PZT) has gained an irreplaceable position as an actuator. In the present work, we specifically compare microwave-sintered PbZr0.52Ti0.48O3 and BaZr0.20Ti0.80O3 ceramics based on their energy-storage capacity. The structural, optical, electrical, ferroelectric, and energy storage properties of microwave-sintered Zr-modified lead titanate (PbZr0.52Ti0.48O3, PZT) and Zr-modified barium titanate (BaZr0.20Ti0.80O3, BZT) ceramics are investigated and addressed. The temperature-dependent dielectric property analysis suggests high transition temperature and dielectric properties for PZT ceramic, whereas the near-room temperature transition is observed in the case of BZT. Furthermore, the band-gap energy value of BZT and PZT from UV–vis spectroscopy indicates the possible use of these ceramics in optoelectronic devices. The ferroelectric properties of PZT and BZT are discussed, and the maximum energy storage capacities are found to be 30.5 and 21 mJ/cm3 for PZT and BZT, respectively. It is found that microwave-sintered PZT’s characteristics make it an attractive option for use in filters, phase shifters, sensors, actuators, and energy-related devices. On the other hand, BZT finds its suitability in biomedical devices and underwater applications.
S. Noormohammad Shareef, Boya Palajonnala Narasaiah, W. Madhuri, K. Vagdevi, and Ramnarayan
EDP Sciences
Carbon Quantum Dots (CQDs) were prepared from modified hydrothermal method using Citric acid and ethane diamine as a source material. The synthesized CQDs were characterized by UV-Vis spectroscopy, Fluorescence Studies (FL), Atomic force microscopy (AFM). The particle size is conformed from Dynamic Light Scattering (DLS) analysis. The synthesized CQDs were doped in polymer blend with various weight percentages and the further characterizations were carried out for X-Ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), dielectric properties, and tensile properties at room temperature and higher temperatures with the help of Universal Testing Mission (UTM). The dielectric behavior of Chitosan/HPMC/CQDs polymer nanocomposites (PNCs) were studied in the range of 50 Hz to 5 MHz frequency and the temperature ranging from 30-100 °C, using LCR meter. The dielectric constant (ε'), dielectric loss (ε') are found with different wt% of CQDs in the PNCs.
Vaishnavi Khade and Madhuri Wuppulluri
Springer Science and Business Media LLC
Avanish Babu Thirumalasetty, Thiyagarajan Krishnan, Siva Kumar Kota Venkata, Srinivas Adiraj, Deepa Xavier, Subramanian Venkatachalam, Rajini Gaddam Kesava Reddy, Zarena Dudekula, and Madhuri Wuppulluri
American Chemical Society (ACS)
Basil Chacko, Avanish Babu Thirumalasetty, Vembakam Vijayakanth, and Madhuri Wuppulluri
American Chemical Society (ACS)
Magnetic hyperthermia is an emerging technique used for the treatment of tumors, where the infected cells will be deactivated using the heat generated from magnetic particles. This study discusses the viability of yttrium iron garnet (YIG) in magnetic hyperthermia treatment. YIG is synthesized using hybrid microwave-assisted hydrothermal and sol–gel auto combustion techniques. The formation of the garnet phase is confirmed using powder X-ray diffraction studies. Further, the morphology and grain size of the material are analyzed and estimated with the help of field emission scanning electron microscopy. Transmittance and optical band gap are obtained using UV–visible spectroscopy. Raman scattering of the material is discussed to understand the phase and vibrational modes. The functional groups of garnet are studied using Fourier transform infrared spectroscopy. Further, the effect of the synthesizing routes on the characteristics of the materials is discussed. A relatively higher magnetic saturation value is observed in the hysteresis loop at room temperature of YIG samples, which is synthesized by a sol–gel auto combustion technique, and it confirms the ferromagnetic behavior. The colloidal stability and surface charge of the prepared YIG are evaluated by a zeta potential measurement. In addition, magnetic induction heating studies are carried out for both prepared samples. The specific absorption rates of 1 mg/mL concentration are 237 and 214 W/g at 35.33 kA/m and 316 kHz field of sol–gel auto combustion and hydrothermal methods, respectively. Due to their higher saturation magnetization of 26.39 emu/g, the sol–gel auto combustion method produced effective YIG and demonstrated superior heating efficiency than the hydrothermally prepared sample. The prepared YIG are biocompatible, and their hyperthermia properties may be explored in various biomedical applications.
NOORMOHAMMAD SHAREEF S and W. Madhuri
Springer Science and Business Media LLC
BaTiO3 (BT)-doped polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) blend nanocomposites are prepared by a simple solution casting method. The PVA/PVP/BT polymer nanocomposites (PNCs) are characterized with Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), UV–Vis spectroscopy and universal testing machine. The dielectric behaviour of PVA/PVP/BT PNCs is studied from 50 to 5 MHz at a temperature ranging from 35 to 155 °C. The C–O, C=O stretching peaks obtained from FTIR results confirm strong miscibility between PVA/PVP and Ti–O bands. The peaks in XRD data disclose the crystalline nature of the filler in the PNCs. From SEM results, good miscibility is found between the polymers and the filler. AFM study reveals increased roughness in the PNCs with an increase in BT%. The absorption spectrum is noticed to have shifted towards higher wavelengths with BT concentration. The dielectric constant (ε′) is found to be maximum for 5 wt% of BT in the PNCs that also exhibited maximum toughness and Young’s modulus.
Vaishnavi Khade, Madhuri Wuppulluri, Arunkumar Chandrasekhar, and T. Avanish Babu
Elsevier
Vaishnavi Khade and Madhuri Wuppulluri
World Scientific Pub Co Pte Ltd
This review reports the latest trends in the ceramic composite matrix used for the magnetoelectric (ME) effect. In the last few years, ME composite has become the center of attraction for use in various electrically and magnetically coupled devices. The growth and use of electronic components everywhere have propulsively accelerated the exploration of self-powered electronic and sensor network devices. ME is a feasible technique for addressing difficulties of traditional batteries such as short life span and frequent recharge difficulties. Self-charging multiferroic components have been found for the constant working of mobile electronics that use multiferroic composites in response to magnetoelectric energy transformation. Researchers have rigorously studied the rigid and flexible magnetoelectric composites for their suitability in applications. This paper gives a comparative study between rigid and flexible magnetoelectric composites based on their properties and provides knowledge about the materials for such types of composites. It reviews the latest polymer-based ME materials as well as the related fabrication and polarization methods. The review finally encapsulates the applications in biomedicine, ranging from mechanical energy harvesters to sensors and actuators.
T. Avanish Babu and W. Madhuri
Royal Society of Chemistry (RSC)
Fabrication of piezoelectric nanogenerators.
T. Avanish Babu and W. Madhuri
Elsevier BV
Basil Chacko, Ashish Roy, A. Melbin Richard, J. Swathy, Babu T. Avanish, and W. Madhuri
Elsevier BV
K. Thiyagarajan, T. Avanish Babu, W. Madhuri, and Arunkumar Chandrasekhar
Elsevier
Ashish Roy, W Madhuri, and Basil Chacko
The Electrochemical Society
The element carbon has been used as a source of energy for the past few hundred years, and now in this era of technology, carbon has played a significant and very prominent role in almost all fields of science and technology. The interesting characteristic of carbon is its ability to form many allotropes due to its valency. In recent decades, various allotropes and forms of carbon have been invented, including fullerenes, carbon nanotubes (CNTs), and graphene. So as an honor to this marvelous element, we humans should know about its various forms of existence. In this present work, we shed light on structural studies of commercially available and self-synthesized carbon nanoparticles. A brief introduction is given to the types, structures, and shapes of the allotropes of carbon for a better understanding. The crystallographic structure of the carbon nanomaterials (CNMs) is investigated by X-ray diffraction (XRD) peak profile analysis. The microstructure is characterized based on crystallite size, interplanar spacing, density, strain, and dislocation density. Raman spectroscopy is particularly well studied to characterize the molecular morphology of CNMs.
S. Prathap and W. Madhuri
Springer Science and Business Media LLC
Pb1-xCoxFe12O19 nano-crystallites with an average crystal diameter varying between 74 and 86 nm are prepared via sol-gel auto-combustion. The X-ray diffraction (XRD) studies confirmed the single-phase P63/mmc space group. The surface morphology of the samples carried out using a field emission scanning electron microscope (FESEM) revealed the long hexagonal structure of the ferrites. Dielectric characterization is studied from room temperature to 800 K and in the frequency range of 100 Hz to 5 MHz. The ferrites exhibited two transition peaks in this temperature region which are attributed to phase transitions between ferroelectric to anti-ferroelectric and anti-ferroelectric to paraelectric phase. The composition x = 0.75 is suitable for high definition television deflection yokes for it has exhibited the highest dielectric constant, low ac electrical conductivity.
S. Prathap, W. Madhuri, and Sher Singh Meena
Elsevier BV
D. Arthisree, W. Madhuri, N. Saravanan, B. Dinesh, S. Saikrithika, and Annamalai Senthil Kumar
Elsevier BV
C. Pavithra, W. Madhuri, and S. Roopas Kiran
Elsevier BV
J. Gurusiddappa, W. Madhuri, K. Priya Dasan, and R. Padma Suvarna
AIP Publishing