Vishal Kumar Chakradhary

About Vishal Kumar Chakradhary

Vishal Kumar Chakradhary, With an exceptional h-index of 10 and a recent h-index of 9 (since 2020), a distinguished researcher at Indian Institute of Technology Kanpur, specializes in the field of Microwave Absorber, EMI shielding, Ferrite, carbon, FSS structure.

His recent articles reflect a diverse array of research interests and contributions to the field:

Superior energy storage performance and excellent multiferroic properties of BaTi1-xGdxO3 (0≤ x≤ 0.06) ceramics

Stress‐induced multiferroic properties of lead‐free (1 − x)BTNO–(x)CFO nanocomposites

Engineering room temperature multiferroicity and temperature dependent dielectric properties of Cr doped BaTiO3 ceramics

Design of Flame-Retardant, Hydrophobic, Ultrathin, Lightweight and Flexible EMI shielding Fabric and Sheets for Defense, Space & Industrial Applications

Physical properties and photocatalytic activity of Cr‐doped TiO2 nanoparticles

Unraveling the effect of Gd doping on the structure, optical, magnetic, dielectric and photocatalytic properties of ZrO2 nanostructures

Compositional disorder and its effect on optical and photocatalytic properties of Ce1−xGdxO2 (0 ≤ x ≤ 0.20) nanostructures

Design and Development of Carbon Nanofiber based Lightweight Flexible Nanocomposite Structure for EMI Shielding Application

Vishal Kumar Chakradhary Information

University

Indian Institute of Technology Kanpur

Position

___

Citations(all)

404

Citations(since 2020)

399

Cited By

88

hIndex(all)

10

hIndex(since 2020)

9

i10Index(all)

10

i10Index(since 2020)

9

Email

University Profile Page

Indian Institute of Technology Kanpur

Vishal Kumar Chakradhary Skills & Research Interests

Microwave Absorber

EMI shielding

Ferrite

carbon

FSS structure

Top articles of Vishal Kumar Chakradhary

Superior energy storage performance and excellent multiferroic properties of BaTi1-xGdxO3 (0≤ x≤ 0.06) ceramics

Authors

M Arshad,Wasi Khan,M Abushad,Samanway Mohanta,Shahid Husain,DK Shukla,Azizurrahaman Ansari,Vishal Kumar Chakradhary

Journal

Materials Research Bulletin

Published Date

2024/1/1

Ceramic based capacitors with superior energy storage performance and high storage energy density play an important role in modern electronic devices. Several ferroelectric materials with high dielectric constant and relaxor behavior become the most promising systems for realizing higher energy storage performance. In the present work, environmentally lead-free BaTi1-xGdxO3 (0 ≤ x ≤ 0.06) nanostructures were synthesized using the sol-gel auto-combustion process. The doping of Gd at the Ti site causes the transformation of the ferroelectric behavior to the relaxor ceramics, which is important for finding the large energy storage efficiency of the material. The surface morphology of undoped and doped samples was examined through the SEM studies. Ferroelectric study evidence that the system is going to a more symmetric phase due to a reduction in the polarization parameters and enhancement in the …

Stress‐induced multiferroic properties of lead‐free (1 − x)BTNO–(x)CFO nanocomposites

Authors

M Arshad,Wasi Khan,M Abushad,M Nadeem,Riyaz,Shahid Husain,DK Shukla,Azizurrahaman Ansari,Vishal Kumar Chakradhary,Shakeel Khan

Journal

Journal of the American Ceramic Society

Published Date

2024/1/30

Multiferroic composites of (1 − x)BaTi0.98Ni0.02O3–(x)CoFe2O4 (0 ≤ x ≤ 0.06) were prepared through conventional solid‐state reaction route. X‐ray diffraction (XRD) studies along with the Rietveld refinement endorse the multiphase nature of the nanocomposite samples. The XRD peaks of the tetragonal bare barium titanate and the inverse cubic spinel of cobalt ferrite nanostructures phase can be identified separately. The tetragonality ratio of the bare barium titanate drops with the addition of the guest material, i.e., cobalt ferrite in the ferroelectric matrix. The Fourier transform infrared (FTIR) spectra confirm the main absorption bands near 540–560 cm−1, corresponding to the metal‐oxide absorption band (ν1 mode), and are related to the stretching modes of the Ti–O bonds. The Raman spectra also signify the two symmetries confirming the nanocomposites’ ferroelectric and ferromagnetic phases. The surface …

Engineering room temperature multiferroicity and temperature dependent dielectric properties of Cr doped BaTiO3 ceramics

Authors

M Arshad,M Abushad,Azizurrahaman Ansari,Vishal Kumar Chakradhary,DK Shukla,Shakeel Khan,Shahid Husain,Wasi Khan

Journal

Journal of Solid State Chemistry

Published Date

2024/1/1

The coexistence of ferroelectricity, ferromagnetism, and piezoelectricity at room temperature in BaTi1-xCrxO3 (0 ≤ x ≤ 0.06) nanostructures is interesting and leads to the multiferroic nature of system. Sol-gel auto-combustion technique has been used for the synthesis of nanostructures. The XRD patterns along with Rietveld refinement analysis, confirm that the samples possess parent tetragonal perovskite structure in the P4mm space group. The oxygen vacancies stoichiometry ratio was estimated through XPS studies. The scanning electron microscopy (SEM) confirms the large grain size in the doped sample. The study of leakage current density reveals an increase in its value with the increase in Cr content due to defects induced in the system. P-E measurements confirm the ferroelectric nature of the samples that diminishes in the doped samples due to the high leakage current. Moreover, the estimated value of …

Design of Flame-Retardant, Hydrophobic, Ultrathin, Lightweight and Flexible EMI shielding Fabric and Sheets for Defense, Space & Industrial Applications

Authors

Vishal Kumar Chakradhary,Swati Gangwar,M Jaleel Akhtar,Kamal K Kar,Shivani Jha

Published Date

2023/12/11

This work presents the fabrication of flame retardant, hydrophobic, lightweight, ultrathin fabric and sheet samples with very high EMI shielding properties. In this study, a PVDF polymer solution with pre-optimized concentrations of highly conductive nanofillers containing exfoliated graphite, carbon nanofiber, and silver nanoparticles is prepared. This conductive polymer solution is directly mold cast to make a sheet sample and the same solution is coated over cotton fabric to make a fabric sample. The FESEM images show the random distribution of nanofillers forming a conductive network, while TGA analysis confirms the high flame retardancy of these samples up to 300°C. The sheet sample shows a high EMI shielding efficiency of more than 37 dB in the complete X-band for a thickness of 0.20 mm as compared to the fabric sample, which shows more than 20 dB shielding efficiency in the complete X-band for a …

Physical properties and photocatalytic activity of Cr‐doped TiO2 nanoparticles

Authors

Yeon-Hum Yun,Jeong-Woo Yun,Soon-Do Yoon,Hun-Soo Byun

Journal

Macromolecular Research

Published Date

2016/1

In this study, nanocomposite films were prepared by using chitosan (CHS), poly(vinyl alcohol) (PVA), titanium oxide (TiO2) nanoparticles, sulfosuccinic acid (SSA) as a crosslinking agent, and sorbitol (SO) and citric acid (CA) as plasticizers. The CHS/PVA nanocomposite films were characterized by X-ray diffraction (XRD), Fourier transform IR spectrophotometry (FTIR), and scanning electronic microscopy (SEM). The results of the XRD and FTIR analysis verified that TiO2 characteristic peaks existed in the prepared nanocomposite films. In addition, the intensity of TiO2 characteristic peaks increased with the increase of TiO2 contents. The physical properties such as tensile strength (TS), elongation at break (%E), swelling behavior (SB), and solubility (S) were investigated. The results indicated that compared with films without added TiO2, the mechanical properties and water resistance were enhanced up to …

Unraveling the effect of Gd doping on the structure, optical, magnetic, dielectric and photocatalytic properties of ZrO2 nanostructures

Authors

Mohammed M Obeid,Hamad R Jappor,Kutaiba Al-Marzoki,Imad Ali Al-Hydary,Shaker J Edrees,Majid M Shukur

Journal

RSC advances

Published Date

2019

The structural, magnetic, and optical properties of the pristine and Gd-doped ZnO nanorods (NRs), prepared by facile thermal decomposition, have been studied using a combination of experimental and density functional theory (DFT) with Hubbard U correction approaches. The XRD patterns demonstrate the single-phase wurtzite structure of the pristine and doped ZnO. The rod-like shape of the nanoparticles has been examined by FESEM and TEM techniques. Elemental compositions of the pure and doped samples were identified by EDX measurement. Due to the Burstein–Moss shift, the optical band gaps of the doped samples have been widened compared to pristine ZnO. The PL spectra show the presence of complex defects. Room temperature magnetic properties have been measured using VSM and revealed the coexistence of paramagnetic and weak ferromagnetic ordering in Gd3+ doped ZnO-NRs. The …

Compositional disorder and its effect on optical and photocatalytic properties of Ce1−xGdxO2 (0 ≤ x ≤ 0.20) nanostructures

Authors

M Abushad,Wasi Khan,M Arshad,Shahid Husain,Azizurrahaman Ansari,Vishal Kumar Chakradhary

Journal

Journal of Materials Science: Materials in Electronics

Published Date

2023/3

In the present work, we have systematically investigated the microstructure, optical, and photocatalytic properties of Ce1−xGdxO2 (0 ≤ x ≤ 0.20) nanostructures. All samples were synthesized using the sol–gel combustion method and characterized by various analytical techniques. The Rietveld refined x-ray diffraction (XRD) patterns confirm face-centered cubic (fcc) fluorite structure of CeO2 with Fm-3m space group in which Ce atom is located at the 4a position surrounded by the eight O (located at 8b) positions. It also endorses the incorporation of Gd3+ at the Ce3+/Ce4+ site by keeping the same crystal structure. The FTIR spectroscopy ensures bending/stretching vibrational modes associated with the functional groups at different wavenumbers. The average particle sizes from transmission electron microscopy (TEM) images for pristine and 7% Gd-doped samples are found to be 14 nm and 30 nm …

Design and Development of Carbon Nanofiber based Lightweight Flexible Nanocomposite Structure for EMI Shielding Application

Authors

Jitendra Tahalyani,M Jaleel Akhtar,Kamal K Kar,Vishal Kumar Chakradhary

Published Date

2022/12/12

The present work deals with design and development of nanocomposite structure of carbon nanofiber CNF (5 to 20 wt%) encapsulated in polyurethane using the solution casting technique. CNF15 nanocomposite (15 wt% CNF in PU) having low density ~0.112g/cm 3 shows the optimized value for conductivity and dielectric properties in the X-band of frequency. The total EMI shielding effectiveness (SET) of the CNF15 nanocomposite structure is above 30 dB covering the entire X-band with its maximum value of ~42.01 dB at 12.4 GHz at just 0.7 mm thick sample. The capacity to handle the complex environment and ability to work for conformal electronic devices is investigated by the measurement SET values after 1 hour of sonication in water, bending at direction and manually bending for 500 mechanical cycles. The EMI shielding mechanism is explained on the basis of dielectric properties and morphology of the …

Origin of enhanced dielectric and multiferroic properties in Pb-doped BaTiO3 ceramics

Authors

M Arshad,M Abushad,M Azhar,Hilal Ahmed,M Nadeem,Azizurrahaman Ansari,Vishal Kumar Chakradhary,Shahid Husain,Wasi Khan

Journal

Applied Physics A

Published Date

2022/12

The ferroelectric and ferromagnetic properties of bare BaTiO3 are weaker than the PbTiO3, which limits its magnetoelectric applications. To overcome these problems, a small amount of Pb was doped in BaTiO3 via a solid-state reaction route to improve the multiferroic properties of the compound. In this way, the modified single-phase Ba1-xPbxTiO3 (0 ≤ x ≤ 0.075) samples have demonstrated improved characteristics and desirable application in the area of microwave tunable devices and multi-layered ceramics capacitors. Rietveld refinement technique ensures that the samples retain their parent perovskite tetragonal phase in P4mm space group. The presence of the metal oxide and several bands were finalized through the Fourier transform infrared (FTIR) spectroscopy study. The elemental composition and the oxygen vacancies were confirmed by the X-ray photoelectron spectroscopy (XPS) studies …

Synthesis and role of structural disorder on the optical, magnetic and dielectric properties of Zn doped NiFe2O4 nanoferrites

Authors

M Abushad,M Arshad,Swaleha Naseem,Hilal Ahmed,Azizurrahaman Ansari,Vishal Kumar Chakradhary,Shahid Husain,Wasi Khan

Journal

Journal of Molecular Structure

Published Date

2022/4/5

Nanoferrites of the chemical formula Ni1-xZnxFe2O4 (0 ≤ x ≤ 0.6) were synthesized via the sol-gel auto combustion process. All the samples were extensively characterized to explore the influence of zinc doping on several physical properties. The detailed analysis of the XRD data confirms the cubic spinel structure of the compositions. The lattice constants and unit cell volume as computed by the Rietveld refinement program are found to follow the Vegard's law. Crystallite sizes of the samples as calculated through Scherrer equation and Williamson-Hall method decrease upon Zn doping in NiFe2O4. The formation of spinel phase was further confirmed by the characteristics bands in FTIR spectra. The well defined spherical morphology and narrow size distribution of the particles together with the purity of synthesized samples were examined by the scanning electron microscopy (SEM) along with energy …

Polaron hopping conduction mechanism and magnetic properties of Pb‐doped LaMnO3

Authors

Faraz A Khan,M Arshad,M Abushad,Swaleha Naseem,Hilal Ahmed,Azizurrahaman Ansari,Vishal Kumar Chakradhary,Shahid Husain,Wasi Khan

Journal

Journal of the American Ceramic Society

Published Date

2022/1

In the present work, we have synthesized La1‐xPbxMno3 (0 ≤ x ≤ 0.20) perovskites through a conventional solid‐state reaction route. The powder x‐ray diffraction data analyzed through the Rietveld refinement program confirm monophase rhombohedral distorted structure (R‐3c space group). Fourier transform infrared spectra exhibit strong and well‐defined absorption bands of a typical perovskite structure. The x‐ray photoelectron spectroscopy studies confirm the elemental composition and oxidation state of various elements in the samples. Low temperature resistivity measurements do not reveal metal–semiconductor transition (MST) in the pristine sample while Pb‐doped samples show MST. The metallic region of the temperature‐dependent resistivity data is well fitted with ρ(T) = ρο + ρ2.5T2.5, which reveals the significance of electron–magnon interaction. Moreover, the semiconducting behavior of all the …

Absorption properties of CNF mixed cobalt nickel ferrite nanocomposite for radar and stealth applications

Authors

Vishal Kumar Chakradhary,M Jaleel Akhtar

Journal

Journal of Magnetism and Magnetic Materials

Published Date

2021/5/1

For the first time, the cobalt doped nickel ferrite/carbon nano-fiber based nanocomposites are synthesized for radar and stealth applications. Initially, the CoxNi1−xFe2O4 with x = 0.0–0.4, nanoparticles are synthesized and then dispersed in the epoxy matrix to investigate their microwave absorption properties. Among all the synthesized nanocomposites, the CoxNi1−xFe2O4, x = 0.4 (55 wt% epoxy) nanocomposite exhibits maximum −10 dB absorption bandwidth of 1.4 GHz only for 10.3 mm thick sample. The synthesized nanocomposite is not suitable to be used for aforementioned application due to high thickness and low absorption bandwidth. To overcome this problem, carbon nanofiber (CNF ~ 1, 2 and 3 wt% epoxy) is added to the earlier synthesized ferrite epoxy system. The nanocomposite sample consisting of CoxNi1−xFe2O4, x = 0.4 (55 wt% epoxy) and CNF (2 wt% epoxy) shows enhanced absorption …

Cross Polarization Minimization by Unit Cell Modification in the FSS Structure Integrated with Carbon Nanocomposite Absorber

Authors

Vishal Kumar Chakradhary,Shubham Juneja,Rakesh Roshan,M Jaleel Akhtar

Published Date

2021/12/17

In this work, a novel cross polarization independent hexagonal ring shape FSS structure is developed to replace old truncated L shaped FSS structure integrated with CB nanocomposite sheet in the hybrid absorbers, proposed in our previous research work, to minimize the cross polar reflection coefficient (RC) [1]. The proposed novel hexagonal ring shape unit cell based FSS structure is combined with 10wt.% CB nanocomposite sheet. The resultant hybrid absorber attained wide absorption bandwidth of 4.1 GHz at 2.6 mm thickness with absorption value varying from 0.9 to 1 in the frequency range 8.88 to 12.98 GHz with negligible PCR value.

Ultrathin and Lightweight Functionalized CNF Mixed Barium Ferrite Nanocomposite for Stealth Applications

Authors

Vishal Kumar Chakradhary,Azizurrahaman Ansari,Himangshu Bhusan Baskey,M Jaleel Akhtar

Published Date

2021/12/17

This work, presents investigation of microwave properties of an advanced magneto-dielectric nanocomposite synthesized by dispersing functionalized carbon nano fiber (CNF 0.0,0.5,1 and 2 wt.parcent) along with barium ferrite nanoparticles (50 wt. %) into epoxy polymer matrix. The FESEM image of nanocomposites showed non-uniform distribution of nanofillers in the epoxy matrix. The real and imaginary part of permittivity increases with increase in CNF concentration, without significantly affecting the magnetic permeability of the nanocomposite samples. Among, all nanocomposites, the 50wt.% nanocomposite samples. Among, all nanocomposites, the 50wt.% wide absorption bandwidth (-10 dB) of 2.50GHz at 1.5mm thickness in X-band.

Correlation between structure, dielectric and multiferroic properties of lead free Ni modified BaTiO3 solid solution

Authors

M Arshad,Wasi Khan,M Abushad,M Nadeem,Shahid Husain,Azizurrahaman Ansari,Vishal Kumar Chakradhary

Journal

Ceramics International

Published Date

2020/12/1

Present study highlights the influence of Ni doping on the structural, optical, dielectric, ferroelectric and magnetic properties of nanocrystalline BaTi1-xNixO3 (0 ≤ x ≤ 0.06) ceramics synthesized by sol-gel auto combustion process. Phase identification and crystal structure are examined through Rietveld refinement analysis that ensures mono-phase nature with tetragonal crystal structure in P4mm space group. The observed variation in the structural parameters viz. lattice constants, unit cell volume, bond lengths (Ti-O) and bond angles (Ti-O-Ti) are the direct evidence of distortion produce in the unit cell under the effect of Ni doping. The FTIR studies confirm perovskite structure and presence of stretching/bending vibrations of the various bands present in the samples. The optical properties divulge a minor alteration in optical bandgap under the influence of Ni content. Dielectric studies reveal higher value of the …

Correlation between EMI shielding and reflection loss mechanism for carbon nanofiber/epoxy nanocomposite

Authors

Vishal Kumar Chakradhary,Shubham Juneja,M Jaleel Akhtar

Journal

Materials Today Communications

Published Date

2020/12/1

The lightweight, carbon nanofibers (CNFs∼1, 2, 2.5, 3, and 4 wt.%) are dispersed into the epoxy matrix to synthesize nanocomposites for microwave absorption and EMI shielding application. The FESEM shows, non-uniform distribution of CNFs in the epoxy matrix. The 2.5 wt.% CNF/epoxy nanocomposite attains a maximum tensile strength of 43.22 MPa. On increasing CNFs concentration, the real part of permittivity increases due to high interfacial polarization, dipolar polarization and nano-capacitance effect, while imaginary part of permittivity increases mainly due to formation of highly conducting 3D network. The 2.5 wt.% CNF/epoxy exhibits maximum reflection loss of -24.46 dB with -10 dB absorption bandwidth of 2.11 GHz at a matching thickness of 1.6 mm. The maximum EMI shielding efficiency value of 12.6 dB is obtained for 4 wt.% CNF/epoxy nanocomposite. The correlation between reflection loss and EMI …

Structural, optical and enhanced multiferroic properties of La/Cr co-substituted BiFeO3 nanostructures

Authors

M Nadeem,Wasi Khan,Shakeel Khan,Shahid Husain,Fouran Singh,Azizurrahaman Ansari,DK Shukla,Abdul Ahad,Vishal Kumar Chakradhary,MJ Akhtar

Journal

Journal of Materials Science Materials in Electronics

Published Date

2020/6/1

We have synthesized BiFeO3 (BFO) and Bi0.5La0.5Fe1−xCrxO3 (0 ≤ x ≤ 0.06) samples via sol–gel process with the objective to explore the influence of La/Cr co-doping on the structural, optical, dielectric and multiferroic properties of BFO. Rietveld refinement analysis and Raman active modes affirm single-phase and rhombohedral crystal structure of the samples in R3c space group. The UV–visible-DRS data reveal a systematic reduction of the bandgap and increase in the Urbach energy (Eu) with the increase of La/Cr content in BFO matrix. The temperature-dependent dielectric measurements divulge that the BFO has the highest dielectric constant, and relaxation peak shifts with the rise in frequency that proposes the possibility of the thermally activated relaxation mechanism which also supported through the Vogel–Fulcher model. The magnetic hysteresis (M–H) loops exhibit ferromagnetic nature of all the …

Highly coercive strontium hexaferrite nanodisks for microwave absorption and other industrial applications

Authors

Vishal Kumar Chakradhary,MJ Akhtar

Journal

Composites Part B: Engineering

Published Date

2020/2/15

Highly coercive strontium hexaferrite (SHF) nanodisks are synthesized for the first time via the polymer solution method. The structural, microstructural, thermal, magnetic, electromagnetic, and microwave absorption properties of the synthesized SHF nanodisks are closely investigated. The Rietveld refinement of the XRD results confirms the crystal structure of the prepared SHF nanodisks as hexagonal with a space group of P63/mmc having cell dimensions of a, b = 5.8808 Å and c = 23.0424 Å with χ2 = 2.48. The thermo-gravimetric behaviour of the synthesized sample shows that the stable phase of SHF nanodisks is formed after 761 °C. The morphological study shows the average diameter and the thickness of the prepared SHF nanodisks as 70 nm and 27 nm, respectively. The SHF nanodisks possess a saturation magnetization of 55.90 emu/g and magnetic coercivity of 10.34 KOe. Such a high coercivity may be …

See List of Professors in Vishal Kumar Chakradhary University(Indian Institute of Technology Kanpur)

Vishal Kumar Chakradhary FAQs

What is Vishal Kumar Chakradhary's h-index at Indian Institute of Technology Kanpur?

The h-index of Vishal Kumar Chakradhary has been 9 since 2020 and 10 in total.

What are Vishal Kumar Chakradhary's top articles?

The articles with the titles of

Superior energy storage performance and excellent multiferroic properties of BaTi1-xGdxO3 (0≤ x≤ 0.06) ceramics

Stress‐induced multiferroic properties of lead‐free (1 − x)BTNO–(x)CFO nanocomposites

Engineering room temperature multiferroicity and temperature dependent dielectric properties of Cr doped BaTiO3 ceramics

Design of Flame-Retardant, Hydrophobic, Ultrathin, Lightweight and Flexible EMI shielding Fabric and Sheets for Defense, Space & Industrial Applications

Physical properties and photocatalytic activity of Cr‐doped TiO2 nanoparticles

Unraveling the effect of Gd doping on the structure, optical, magnetic, dielectric and photocatalytic properties of ZrO2 nanostructures

Compositional disorder and its effect on optical and photocatalytic properties of Ce1−xGdxO2 (0 ≤ x ≤ 0.20) nanostructures

Design and Development of Carbon Nanofiber based Lightweight Flexible Nanocomposite Structure for EMI Shielding Application

...

are the top articles of Vishal Kumar Chakradhary at Indian Institute of Technology Kanpur.

What are Vishal Kumar Chakradhary's research interests?

The research interests of Vishal Kumar Chakradhary are: Microwave Absorber, EMI shielding, Ferrite, carbon, FSS structure

What is Vishal Kumar Chakradhary's total number of citations?

Vishal Kumar Chakradhary has 404 citations in total.

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