GANESH SHRIDHAR HEGDE
@klesnc.edu.in
Assistant Professor Department of Physics
KLE S Nijalingappa College
Dr. Ganesh Shridhar Hegde
Ph.D., M.Sc.
Assistant Professor
Dept of Physics
Post Graduate Centre
KLE Society’s S Nijalingappa College
#1040, II Block, Rajajinagar,
Bengaluru-560010
Phone: 080 23526055 / 23325020
Proper home address
Post gudeangadi
Kumta
Uttara Kannada
India.
Phone: 8277049441
e-mail: ganeshhegde358@
Personal information
Date of Birth : 10-01-1995
Nationality : Indian
Gender : Male
Marital status : Single
Languages known : English, Kannada (Mother tongue), Hindi, Marathi
Present address : Post Rajajinagar, Banglore 560010
Permanent address : Post Gudeangadi, Kumta, hireoni cross,
Uttara Kannada, 581351
EDUCATION
1) Ph. D.
Awarded on 15th Sept 2022
Department of Physics
MIT, MAHE, Manipal
2)M.Sc. in Physics (Astrophysics)
Dept of Physics
Fergusson college affiliated to Savitribai Pule Pune University
RESEARCH, TEACHING, or OTHER INTERESTS
Materials Science, Physics and Astronomy, Condensed Matter Physics, Astronomy and Astrophysics
Scopus Publications
Scopus Publications
Swaraangi Shirodkar, A. N. Prabhu, Suchitra Putran, Ashok Rao, U. Deepika Shanubhogue, and Ganesh Shridhar Hegde
Springer Science and Business Media LLC
AbstractIn recent years, thermoelectricity has gained popularity as a renewable energy source, with applications including Peltier coolers and thermoelectric generators, particularly focusing on materials, like bismuth telluride and its doped derivatives. This study investigates Bi2Te3, (Bi0.98Ge0.02)2Te2.7Se0.3, and (Bi0.98Ge0.02)2Te2.7Se0.3/Bi2Te3 synthesized via solid-state reaction, revealing a rhombohedral structure in the XRD pattern and confirming chemical composition and composite homogeneity through EDS and porosity, density, and selenium integration via FESEM. Electrical resistivity decreases with rising temperature, while the Seebeck coefficient shows a linear increase, indicating n-type semiconductor behaviour. The highest power factor of 108 μW/mK2 is achieved by (Bi0.98Ge0.02)2Te2.7Se0.3, contrasting with the lowest of 20 μW/mK2 observed for the pristine sample at 250 °C. Ge atoms enhance the power factor of (Bi0.98Ge0.02)2Te2.7Se0.3 by 5.4 times compared to the pristine compound, making it ideal for thermoelectric applications through acceptor behaviour and defect engineering.
Vivekananda, P. K. Prarthana, M. Archana, R Gowrishree, Tejashree Bhat, V Prakruthi, N. S. Keerthana, P. Sharath, T. Tabassum Sulthana, R. Thulasi,et al.
Springer Science and Business Media LLC
Ganesh Shridhar Hegde, A. N. Prabhu, Suchitra Putran, Megha Y. Bhat, and P. D. Babu
Springer Science and Business Media LLC
AbstractThe present study examines the thermoelectric (TE) properties of Polyaniline (PANI) in (Bi0.98In0.02)2Te2.7Se0.3 (BIT) and (Bi0.98In0.02)2Se2.7Te0.3 (BIS), compounds created using solid-state reaction in the temperature interval 10 to 350 K. The XRD study reveals hexagonal crystal structure with a space group of $$R\\stackrel{-}{3}m$$ R 3 - m . The composite samples have grains that resemble hair like structure because size of the grains above the surfaces has expanded irregularly, and selenium has been shown to concentrate at the grain borders. Electrical resistivity in BIS/PANI has found decreased by 6 times compared to BIT/PANI. The decrease in overall thermal conductivity is strongly influenced by the interface scattering effect of PANI composites and the BIT/BIS grain boundaries. The thermal conductivity of pure BIT is found to decrease by 1.5 and 1.4 times, respectively, than that of BIT/PANI and BIS/PANI. In comparison to pure BIT and BIS samples, the ZT value of BIT/PANI has been raised by a factor of 20.
Ganesh Shridhar Hegde, A. N. Prabhu, Suchitra Putran, Ashok Rao, K. Gurukrishna, and U. Deepika Shanubhogue
Springer Science and Business Media LLC
AbstractBy using the solid-state reaction approach, composite polycrystalline samples of (Bi0.98In0.02)2Te2.7Se0.3/x%Bi2Se3 were created with varying amounts of Bi2Se3, (x = 5%, 10%, 15%, and 20%). The hexagonal crystal structure of the composite was revealed by x-ray diffraction (XRD) with a space group of R$$\\overline{3 }$$ 3 ¯ m. The surface of the samples was seen to have secondary particles using a field emission scanning electronic microscope. Every sample displayed the typical semi-conducting behaviour across the entire temperature range. In the complex (Bi0.98In0.02)2Te2.7Se0.3, it was found that bismuth was coordinated with six selenium atoms and there were significant selenium vacancies. With an increase in bismuth selenide concentration, the dissolution pattern shifted to a substitutional pattern. A two fold decrease in electrical resistivity for (Bi0.98In0.02)2Te2.7Se0.3/20%Bi2Se3 composition was seen compared to (Bi0.98In0.02)2Te2.7Se0.3/5%Bi2Se3. The granular material was produced by sintering and scattering of potential barrier, a thermal process that increases the Seebeck coefficient. A 200% increase was observed in thermopower for (Bi0.98In0.02)2Te2.7Se0.3/20%Bi2Se3 compared to (Bi0.98In0.02)2Te2.7Se0.3/5%Bi2Se3 compound. Graphical Abstract
Ganesh Shridhar Hegde, A. N. Prabhu, and M. K. Chattopadhyay
Springer Science and Business Media LLC
AbstractThe melt-grown, indium and selenium co-doped Bi2Te3 single-crystal system is studied with a purpose to improve and analyze the thermoelectric performance in the low and near room-temperature range (10–400 K). The influence of co-dopants on the crystalline perfection, symmetry, dislocation, and single-crystal quality is investigated using high-resolution X-ray diffraction. The surface morphological features show the existence of small-angle grain boundaries, white patches, and tilt boundaries. Degenerate type of semiconducting behavior is seen in all the samples over the entire temperature range. The existence of small polarons is experimentally inferred from temperature-dependent electrical resistivity. Measurement of Seebeck coefficient confirms p- to n-type transition in the crystals doped with indium and selenium. The total thermal conductivity at 11 K was decreased by 3.4 times in (Bi0.98In0.02)2Te2.7Se0.3 as compared to pristine sample. Therefore, this novel co-doped indium and selenium Bi2Te3 single-crystal combination is viable to use as a competitor for low and near-room-temperature thermoelectric applications.
Ganesh Shridhar Hegde, A. N. Prabhu, Ashok Rao, K. Gurukrishna, and U. Deepika Shanubhogue
Springer Science and Business Media LLC
AbstractPolycrystalline composite samples of (Bi0.98In0.02)2Se2.7Te0.3/Bi2Te3 with different concentrations of Bi2Te3 such as 5%,10%,15% and 20% were prepared by the solid-state reaction technique. The X-Ray diffraction analysis has shown the hexagonal composite crystal structure with space group of $$R\\overline{3 }$$ R 3 ¯ m. Field emission scanning electronic microscope shows secondary particles on the surface of the samples. All the samples have shown the usual semi-conducting behaviour throughout the temperature range. It is observed that bismuth has been co-ordinated with 6 selenium atoms in (Bi0.98In0,02)2Se2.7Te0.3 compound and it has enormous selenium vacancies. The electrical resistivity represents the noteworthy result of the grain boundaries leading to the higher content of scattering centres in the polycrystalline composite samples. It is found that the electronegativity differences of In and Te, In and Se are less than Bi and Se, Bi and Te is the reason for the decrease in Seebeck coefficient in the compound containing 15% and 20% of Bi2Te3.
Ganesh Shridhar Hegde and A. N. Prabhu
Springer Science and Business Media LLC
AbstractOne of the global demands of primary research objectives is to achieve human energy harvesting and self-powered wearable technologies. Bismuth chalcogenides are the trending materials for thermoelectric generators and Peltier coolers due to their notable thermoelectric figure of merit in the low- and room-temperature range. Systematic alloying of bismuth chalcogenides leads to a substantial change in their electrical and thermal transport properties. The high thermoelectric figure of merit (ZT) observed in bismuth chalcogenides is due to the rhombohedral crystal structure, lower effective mass, low thermal conductivity, and large band degeneracy. This review is aimed at identifying and quantifying different techniques for effectively improving the thermoelectric properties of doped/composite bismuth chalcogenide compounds. The review also examines the various synthesis methods including ball milling (BM), spark plasma sintering (SPS), self-propagating high-temperature synthesis (SHS), soft chemical reaction, hydrothermal reaction, melt growth (MG), melt spinning (MS), sintering and consolidated synthesis, and hot extrusion, with their respective figures of merit. Since device modification is a challenging task, this report reviews the present research on bismuth chalcogenide alloys to benchmark future development using various techniques. Graphical Abstract
Ganesh Shridhar Hegde, A.N. Prabhu, C.F. Yang, and Y.K. Kuo
Elsevier BV
Ganesh Shridhar Hegde, Vinay Parol, Ashok Rao, A.N. Prabhu, Joshua J.B. Levinsky, and Graeme R. Blake
Elsevier BV
Ganesh Shridhar Hegde, A. N. Prabhu, and M. K. Chattopadhyay
Springer Science and Business Media LLC
AbstractIn the current work, growth and thermoelectric characterization of tin and selenium co-doped single crystal bismuth telluride have been carried out in the range of temperature 10–400 K. The crystals show hexagonal crystal structure with R$$\\overline{3 }$$ 3 ¯ m space group. The direction of growth, quality of the single crystals, the density of dislocation, and dopants effect on the inner plane structure of the crystals have been analyzed through high-resolution X-ray diffraction study. Energy dispersive analysis of X-rays approves the elemental composition, and field emission scanning electron microscopy shows uniform growth with micro precipitates on the surface of the crystals. Quasi degenerate and non-degenerate electrical resistivity is observed in the pristine and doped samples, respectively. Temperature-dependent Seebeck coefficient measurements confirm the n-type semiconducting nature of the pristine as well as doped samples. Temperature-dependent power factor of (Bi0.96Sn0.04)2Te2.7Se0.3 is found to increase by 1.1 times, and electrical resistivity reduced by 3.3 times as compared to pristine Bi2Te3.
Ganesh Shridhar Hegde, A.N. Prabhu, Y.H. Gao, Y.K. Kuo, and V. Raghavendra Reddy
Elsevier BV
Ganesh Shridhar Hegde, A.N. Prabhu, Ashok Rao, and M.K. Chattopadhyay
Elsevier BV
Ganesh Shridhar Hegde, A. N. Prabhu, R. Y. Huang, and Y. K. Kuo
Springer Science and Business Media LLC
AbstractPolycrystalline samples of (Bi1-xInx)2Se2.7Te0.3 (x = 0.00, 0.02, and 0.04) were prepared by the solid-state reaction technique. X-ray diffraction pattern confirms that the polycrystalline samples have a hexagonal structure with spacegroup R$$\\stackrel{-}{3}$$ 3 - m. The surface morphologic study reveals the existence of porous behavior in the studied samples due to the volatilization of Selenium. Energy dispersive X-ray analysis validates the expected and observed elemental composition of the samples. Electrical resistivity has shown metallic behavior. Hall effect and Seebeck coefficient measurements indicate the p-type and n-type conduction for the pristine sample Bi2Se3 and the (Bi1-xInx)2Se2.7Te0.3 samples, respectively. The thermal conductivity and electrical resistivity were found to reduce by 7.5 and 9 times, respectively, for (Bi0.96In0.04)2Se2.7Te0.3 compared to the pristine sample Bi2Se3.
Ganesh Shridhar Hegde, A.N. Prabhu, Ashok Rao, and P.D. Babu
Elsevier BV
Vinay Parol, V. Upadhyaya, Ganesh Shridhar Hegde, N.K. Lokanath, and A.N. Prabhu
Elsevier BV
RECENT SCHOLAR PUBLICATIONS
Publications
1 Enhancement of thermoelectric performance of In doped
compounds Hegde, Ganesh Shridhar, A. N. Prabhu, Ashok Rao, and P. D. Babu Physica B: Condensed Matter 584 412087 2020 2.436
2 Reduction in thermal conductivity and electrical
resistivity of indium and tellurium co-doped bismuth
selenide thermoelectric system Hegde, G. S., Prabhu, A. N., Huang, R. Y., & Kuo, Y. K. Journal of Materials and Materials in Electronics 31 19525 2020 2.47
3 Potential thermoelectric materials of indium and tellurium co-doped
bismuth selenide single crystals grown by melt growth technique Hegde, G. S., Prabhu, A. N., Gao, Y. H., Kuo, Y. K., & Reddy, V. R Journal of Alloys and Compounds 866 158814 2021 5.316
4 Enhancement in thermoelectric figure of merit of bismuth telluride system
Hegde,Ganesh Shridhar, A. N. Prabhu, Ashok Rao, and M. K. Chattopadhyay. Materials Science and Semiconductor Processing 127 105645 2021 3.97
5 Improved electrical conductivity and power factor in Sn
and Se co-doped melt- grown Bi2Te3 single crystal Hegde, Ganesh Shridhar, A. N. Prabhu, and M. K. Chattopadhyay. Journal of Materials Science and Materials in Electronics 20 24871 2021 2.47
6 Reduction in electrical resistivity of bismuth selenide single crystal via Sn
and Te co-doping Hegde, Ganesh Shridhar, A. N. Prabhu, R. Y. Huang, and Y. K. Kuo Materials Chemistry and Physics 278 125675 2022 4.094
7 A Review on Doped/Composite Bismuth Chalcogenide Compounds
for Thermoelectric Device Applications: Various
GRANT DETAILS
Synthesis and thermoelectric Characterization of In/Sn/Ge
doped Bismuth Chalcogenide films prepared by DC magnetron
sputtering
Funding Agency: UGC DAE CSR MUMBAI
150000
CRS/2022-23/03/879