---
_id: '14828'
abstract:
- lang: eng
  text: Production of hydrogen at large scale requires development of non-noble, inexpensive,
    and high-performing catalysts for constructing water-splitting devices. Herein,
    we report the synthesis of Zn-doped NiO heterostructure (ZnNiO) catalysts at room
    temperature via a coprecipitation method followed by drying (at 80 °C, 6 h) and
    calcination at an elevated temperature of 400 °C for 5 h under three distinct
    conditions, namely, air, N2, and vacuum. The vacuum-synthesized catalyst demonstrates
    a low overpotential of 88 mV at −10 mA cm–2 and a small Tafel slope of 73 mV dec–1
    suggesting relatively higher charge transfer kinetics for hydrogen evolution reactions
    (HER) compared with the specimens synthesized under N2 or O2 atmosphere. It also
    demonstrates an oxygen evolution (OER) overpotential of 260 mV at 10 mA cm–2 with
    a low Tafel slope of 63 mV dec–1. In a full-cell water-splitting device, the vacuum-synthesized
    ZnNiO heterostructure demonstrates a cell voltage of 1.94 V at 50 mA cm–2 and
    shows remarkable stability over 24 h at a high current density of 100 mA cm–2.
    It is also demonstrated in this study that Zn-doping, surface, and interface engineering
    in transition-metal oxides play a crucial role in efficient electrocatalytic water
    splitting. Also, the results obtained from density functional theory (DFT + U
    = 0–8 eV), where U is the on-site Coulomb repulsion parameter also known as Hubbard
    U, based electronic structure calculations confirm that Zn doping constructively
    modifies the electronic structure, in both the valence band and the conduction
    band, and found to be suitable in tailoring the carrier’s effective masses of
    electrons and holes. The decrease in electron’s effective masses together with
    large differences between the effective masses of electrons and holes is noticed,
    which is found to be mainly responsible for achieving the best water-splitting
    performance from a 9% Zn-doped NiO sample prepared under vacuum.
acknowledgement: This work was supported by the Technology Innovation Program (20011622,
  Development of Battery System Applied High-Efficiency Heat Control Polymer and Part
  Component) funded by the Ministry of Trade, Industry & Energy (MOTIE, Korea). Author
  acknowledge to Prof. Tsunehiro Takeuchi from Toyota Technological Institute, Nagoya,
  Japan for the support of computational resources.
article_processing_charge: No
article_type: original
author:
- first_name: Gundegowda Kalligowdanadoddi
  full_name: Kiran, Gundegowda Kalligowdanadoddi
  last_name: Kiran
- first_name: Saurabh
  full_name: Singh, Saurabh
  id: 12d625da-9cb3-11ed-9667-af09d37d3f0a
  last_name: Singh
  orcid: 0000-0003-2209-5269
- first_name: Neelima
  full_name: Mahato, Neelima
  last_name: Mahato
- first_name: Thupakula Venkata Madhukar
  full_name: Sreekanth, Thupakula Venkata Madhukar
  last_name: Sreekanth
- first_name: Gowra Raghupathy
  full_name: Dillip, Gowra Raghupathy
  last_name: Dillip
- first_name: Kisoo
  full_name: Yoo, Kisoo
  last_name: Yoo
- first_name: Jonghoon
  full_name: Kim, Jonghoon
  last_name: Kim
citation:
  ama: Kiran GK, Singh S, Mahato N, et al. Interface engineering modulation combined
    with electronic structure modification of Zn-doped NiO heterostructure for efficient
    water-splitting activity. <i>ACS Applied Energy Materials</i>. 2024;7(1):214-229.
    doi:<a href="https://doi.org/10.1021/acsaem.3c02519">10.1021/acsaem.3c02519</a>
  apa: Kiran, G. K., Singh, S., Mahato, N., Sreekanth, T. V. M., Dillip, G. R., Yoo,
    K., &#38; Kim, J. (2024). Interface engineering modulation combined with electronic
    structure modification of Zn-doped NiO heterostructure for efficient water-splitting
    activity. <i>ACS Applied Energy Materials</i>. American Chemical Society. <a href="https://doi.org/10.1021/acsaem.3c02519">https://doi.org/10.1021/acsaem.3c02519</a>
  chicago: Kiran, Gundegowda Kalligowdanadoddi, Saurabh Singh, Neelima Mahato, Thupakula
    Venkata Madhukar Sreekanth, Gowra Raghupathy Dillip, Kisoo Yoo, and Jonghoon Kim.
    “Interface Engineering Modulation Combined with Electronic Structure Modification
    of Zn-Doped NiO Heterostructure for Efficient Water-Splitting Activity.” <i>ACS
    Applied Energy Materials</i>. American Chemical Society, 2024. <a href="https://doi.org/10.1021/acsaem.3c02519">https://doi.org/10.1021/acsaem.3c02519</a>.
  ieee: G. K. Kiran <i>et al.</i>, “Interface engineering modulation combined with
    electronic structure modification of Zn-doped NiO heterostructure for efficient
    water-splitting activity,” <i>ACS Applied Energy Materials</i>, vol. 7, no. 1.
    American Chemical Society, pp. 214–229, 2024.
  ista: Kiran GK, Singh S, Mahato N, Sreekanth TVM, Dillip GR, Yoo K, Kim J. 2024.
    Interface engineering modulation combined with electronic structure modification
    of Zn-doped NiO heterostructure for efficient water-splitting activity. ACS Applied
    Energy Materials. 7(1), 214–229.
  mla: Kiran, Gundegowda Kalligowdanadoddi, et al. “Interface Engineering Modulation
    Combined with Electronic Structure Modification of Zn-Doped NiO Heterostructure
    for Efficient Water-Splitting Activity.” <i>ACS Applied Energy Materials</i>,
    vol. 7, no. 1, American Chemical Society, 2024, pp. 214–29, doi:<a href="https://doi.org/10.1021/acsaem.3c02519">10.1021/acsaem.3c02519</a>.
  short: G.K. Kiran, S. Singh, N. Mahato, T.V.M. Sreekanth, G.R. Dillip, K. Yoo, J.
    Kim, ACS Applied Energy Materials 7 (2024) 214–229.
date_created: 2024-01-17T12:48:35Z
date_published: 2024-01-08T00:00:00Z
date_updated: 2025-07-22T14:07:29Z
day: '08'
department:
- _id: MaIb
doi: 10.1021/acsaem.3c02519
external_id:
  isi:
  - '001138342900001'
  oaworkID:
  - w4389780443
intvolume: '         7'
isi: 1
issue: '1'
keyword:
- Electrical and Electronic Engineering
- Materials Chemistry
- Electrochemistry
- Energy Engineering and Power Technology
- Chemical Engineering (miscellaneous)
language:
- iso: eng
month: '01'
oa_version: None
oaworkID: 1
page: 214-229
publication: ACS Applied Energy Materials
publication_identifier:
  issn:
  - 2574-0962
publication_status: published
publisher: American Chemical Society
quality_controlled: '1'
scopus_import: '1'
status: public
title: Interface engineering modulation combined with electronic structure modification
  of Zn-doped NiO heterostructure for efficient water-splitting activity
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 7
year: '2024'
...
---
_id: '14379'
abstract:
- lang: eng
  text: We report on a simple surfactant/template free chemical route for the synthesis
    of semi-polycrystalline polyaniline-graphite (SPani-graphite) composite and its
    application as an electroactive material in electrochemical charge storage. The
    synthesized material exhibits well-defined poly-crystallographic lattices in high
    resolution transmission electron micrographs and sharp peaks in x-ray diffraction
    spectra suggesting crystalline nature of the material. The specific capacitance
    computed from the galvanostatic charge-discharge (GCD) data obtained from 3-electrode
    cell configuration using 1 M aq. Na2SO4 as an electrolyte was 111.4 F g−1 at a
    current density of 0.1 A g−1 which rises to 269 F g−1 at an elevated current density
    of 1.0 A g−1. A similar pattern of increase in the specific capacitance values
    with an increase in the current density was observed in the results obtained from
    2-electrode symmetric device configuration using polymer gel electrolyte (xanthan
    gum in 1 M aq. Na2SO4). The specific capacitance computed from the GCD data obtained
    from the device configuration was 20 F g−1 at the current density of 1.0 A g−1.
    The device delivers an energy density of 1.7 Wh kg−1 and a power density of 2.48
    kWh kg−1 at an applied current density of 0.5 A g−1 suggesting an excellent rate
    capability and power management. In addition, the device exhibits ⁓92 % specific
    capacitance retention up to 8000 continuous GCD cycles and ⁓80 % coulombic efficiency
    up to 10,000 continuous GCD cycles indicating excellent cycling stability. The
    unique feature of increasing specific capacitance with respect to applied current
    density is attributed to the presence of semi-polycrystalline phases in the SPani-graphite
    matrix. The material behaves as a surface redox supercapacitor and its unique
    mechanism of charge storage is discussed in detail in the article.
acknowledgement: This work was supported by 2023 Yeungnam University Research Grant.
article_number: '117463'
article_processing_charge: No
article_type: original
author:
- first_name: Neelima
  full_name: Mahato, Neelima
  last_name: Mahato
- first_name: Saurabh
  full_name: Singh, Saurabh
  id: 12d625da-9cb3-11ed-9667-af09d37d3f0a
  last_name: Singh
  orcid: 0000-0003-2209-5269
- first_name: Mohammad
  full_name: Faisal, Mohammad
  last_name: Faisal
- first_name: T. V.M.
  full_name: Sreekanth, T. V.M.
  last_name: Sreekanth
- first_name: Sutripto
  full_name: Majumder, Sutripto
  last_name: Majumder
- first_name: Kisoo
  full_name: Yoo, Kisoo
  last_name: Yoo
- first_name: Jonghoon
  full_name: Kim, Jonghoon
  last_name: Kim
citation:
  ama: Mahato N, Singh S, Faisal M, et al. Polycrystalline phases grown in-situ engendering
    unique mechanism of charge storage in polyaniline-graphite composite. <i>Synthetic
    Metals</i>. 2023;299. doi:<a href="https://doi.org/10.1016/j.synthmet.2023.117463">10.1016/j.synthmet.2023.117463</a>
  apa: Mahato, N., Singh, S., Faisal, M., Sreekanth, T. V. M., Majumder, S., Yoo,
    K., &#38; Kim, J. (2023). Polycrystalline phases grown in-situ engendering unique
    mechanism of charge storage in polyaniline-graphite composite. <i>Synthetic Metals</i>.
    Elsevier. <a href="https://doi.org/10.1016/j.synthmet.2023.117463">https://doi.org/10.1016/j.synthmet.2023.117463</a>
  chicago: Mahato, Neelima, Saurabh Singh, Mohammad Faisal, T. V.M. Sreekanth, Sutripto
    Majumder, Kisoo Yoo, and Jonghoon Kim. “Polycrystalline Phases Grown In-Situ Engendering
    Unique Mechanism of Charge Storage in Polyaniline-Graphite Composite.” <i>Synthetic
    Metals</i>. Elsevier, 2023. <a href="https://doi.org/10.1016/j.synthmet.2023.117463">https://doi.org/10.1016/j.synthmet.2023.117463</a>.
  ieee: N. Mahato <i>et al.</i>, “Polycrystalline phases grown in-situ engendering
    unique mechanism of charge storage in polyaniline-graphite composite,” <i>Synthetic
    Metals</i>, vol. 299. Elsevier, 2023.
  ista: Mahato N, Singh S, Faisal M, Sreekanth TVM, Majumder S, Yoo K, Kim J. 2023.
    Polycrystalline phases grown in-situ engendering unique mechanism of charge storage
    in polyaniline-graphite composite. Synthetic Metals. 299, 117463.
  mla: Mahato, Neelima, et al. “Polycrystalline Phases Grown In-Situ Engendering Unique
    Mechanism of Charge Storage in Polyaniline-Graphite Composite.” <i>Synthetic Metals</i>,
    vol. 299, 117463, Elsevier, 2023, doi:<a href="https://doi.org/10.1016/j.synthmet.2023.117463">10.1016/j.synthmet.2023.117463</a>.
  short: N. Mahato, S. Singh, M. Faisal, T.V.M. Sreekanth, S. Majumder, K. Yoo, J.
    Kim, Synthetic Metals 299 (2023).
date_created: 2023-10-01T22:01:13Z
date_published: 2023-11-01T00:00:00Z
date_updated: 2024-01-30T13:55:50Z
day: '01'
department:
- _id: MaIb
doi: 10.1016/j.synthmet.2023.117463
external_id:
  isi:
  - '001083568900001'
intvolume: '       299'
isi: 1
language:
- iso: eng
month: '11'
oa_version: None
publication: Synthetic Metals
publication_identifier:
  issn:
  - 0379-6779
publication_status: published
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Polycrystalline phases grown in-situ engendering unique mechanism of charge
  storage in polyaniline-graphite composite
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 299
year: '2023'
...
---
_id: '14652'
abstract:
- lang: eng
  text: In order to demonstrate the stability of newly proposed iridium-based Ir2Cr(In,Sn)
    and IrRhCr(In,Sn) heusler alloys, we present ab-initio analysis of these alloys
    by examining various properties to prove their stability. The stability of these
    alloys can be inferred from different cohesive and formation energies as well
    as positive phonon frequencies. Their electronic structure results indicate that
    they are semi-metals in nature. The magnetic moments are computed using the Slater-Pauling
    formula and exhibit a high value, with the Cr atom contributing the most in all
    alloys. Mulliken’s charge analysis results show that our alloys contain a range
    of linkages, mainly ionic and covalent ones. The ductility and mechanical stability
    of these alloys are confirmed by elastic constants viz. Poisson’s ratio, Pugh’s
    ratio, and many different types of elastic moduli.
article_number: '415539'
article_processing_charge: No
article_type: original
author:
- first_name: Shyam Lal
  full_name: Gupta, Shyam Lal
  last_name: Gupta
- first_name: Saurabh
  full_name: Singh, Saurabh
  id: 12d625da-9cb3-11ed-9667-af09d37d3f0a
  last_name: Singh
  orcid: 0000-0003-2209-5269
- first_name: Sumit
  full_name: Kumar, Sumit
  last_name: Kumar
- first_name: Unknown
  full_name: Anupam, Unknown
  last_name: Anupam
- first_name: Samjeet Singh
  full_name: Thakur, Samjeet Singh
  last_name: Thakur
- first_name: Ashish
  full_name: Kumar, Ashish
  last_name: Kumar
- first_name: Sanjay
  full_name: Panwar, Sanjay
  last_name: Panwar
- first_name: D.
  full_name: Diwaker, D.
  last_name: Diwaker
citation:
  ama: 'Gupta SL, Singh S, Kumar S, et al. Ab-initio stability of Iridium based newly
    proposed full and quaternary heusler alloys. <i>Physica B: Condensed Matter</i>.
    2023;674. doi:<a href="https://doi.org/10.1016/j.physb.2023.415539">10.1016/j.physb.2023.415539</a>'
  apa: 'Gupta, S. L., Singh, S., Kumar, S., Anupam, U., Thakur, S. S., Kumar, A.,
    … Diwaker, D. (2023). Ab-initio stability of Iridium based newly proposed full
    and quaternary heusler alloys. <i>Physica B: Condensed Matter</i>. Elsevier. <a
    href="https://doi.org/10.1016/j.physb.2023.415539">https://doi.org/10.1016/j.physb.2023.415539</a>'
  chicago: 'Gupta, Shyam Lal, Saurabh Singh, Sumit Kumar, Unknown Anupam, Samjeet
    Singh Thakur, Ashish Kumar, Sanjay Panwar, and D. Diwaker. “Ab-Initio Stability
    of Iridium Based Newly Proposed Full and Quaternary Heusler Alloys.” <i>Physica
    B: Condensed Matter</i>. Elsevier, 2023. <a href="https://doi.org/10.1016/j.physb.2023.415539">https://doi.org/10.1016/j.physb.2023.415539</a>.'
  ieee: 'S. L. Gupta <i>et al.</i>, “Ab-initio stability of Iridium based newly proposed
    full and quaternary heusler alloys,” <i>Physica B: Condensed Matter</i>, vol.
    674. Elsevier, 2023.'
  ista: 'Gupta SL, Singh S, Kumar S, Anupam U, Thakur SS, Kumar A, Panwar S, Diwaker
    D. 2023. Ab-initio stability of Iridium based newly proposed full and quaternary
    heusler alloys. Physica B: Condensed Matter. 674, 415539.'
  mla: 'Gupta, Shyam Lal, et al. “Ab-Initio Stability of Iridium Based Newly Proposed
    Full and Quaternary Heusler Alloys.” <i>Physica B: Condensed Matter</i>, vol.
    674, 415539, Elsevier, 2023, doi:<a href="https://doi.org/10.1016/j.physb.2023.415539">10.1016/j.physb.2023.415539</a>.'
  short: 'S.L. Gupta, S. Singh, S. Kumar, U. Anupam, S.S. Thakur, A. Kumar, S. Panwar,
    D. Diwaker, Physica B: Condensed Matter 674 (2023).'
date_created: 2023-12-10T23:00:56Z
date_published: 2023-11-28T00:00:00Z
date_updated: 2023-12-12T08:22:23Z
day: '28'
department:
- _id: MaIb
doi: 10.1016/j.physb.2023.415539
intvolume: '       674'
language:
- iso: eng
month: '11'
oa_version: None
publication: 'Physica B: Condensed Matter'
publication_identifier:
  issn:
  - 0921-4526
publication_status: epub_ahead
publisher: Elsevier
quality_controlled: '1'
scopus_import: '1'
status: public
title: Ab-initio stability of Iridium based newly proposed full and quaternary heusler
  alloys
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 674
year: '2023'
...
---
_id: '14777'
abstract:
- lang: eng
  text: The effects of the partial V-substitution for Ag on the thermoelectric (TE)
    properties are investigated for a flexible semiconducting compound Ag2S0.55Se0.45.
    Density functional theory calculations predict that such a partial V-substitution
    constructively modifies the electronic structure near the bottom of the conduction
    band to improve the TE performance. The synthesized Ag1.97V0.03S0.55Se0.45 is
    found to possess a TE dimensionless figure-of-merit (ZT) of 0.71 at 350 K with
    maintaining its flexible nature. This ZT value is relatively high in comparison
    with those reported for flexible TE materials below 360 K. The increase in the
    ZT value is caused by the enhanced absolute value of the Seebeck coefficient with
    less significant variation in electrical resistivity. The high ZT value with the
    flexible nature naturally allows us to employ the Ag1.97V0.03S0.55Se0.45 as a
    component of flexible TE generators.
acknowledgement: This work received financial support partially from Japan Science
  and Technology Agency (JST) CREST Grant No. JPMJCR18I2, Japan. The powder-XRD experiments
  were conducted at BL5S2 of Aichi Synchrotron Radiation Center, Aichi Science & Technology
  Foundation, Aichi, Japan (Proposal No. 202301057).
article_number: '125206'
article_processing_charge: Yes
article_type: original
author:
- first_name: Kosuke
  full_name: Sato, Kosuke
  last_name: Sato
- first_name: Saurabh
  full_name: Singh, Saurabh
  id: 12d625da-9cb3-11ed-9667-af09d37d3f0a
  last_name: Singh
  orcid: 0000-0003-2209-5269
- first_name: Itsuki
  full_name: Yamazaki, Itsuki
  last_name: Yamazaki
- first_name: Keisuke
  full_name: Hirata, Keisuke
  last_name: Hirata
- first_name: Artoni Kevin R.
  full_name: Ang, Artoni Kevin R.
  last_name: Ang
- first_name: Masaharu
  full_name: Matsunami, Masaharu
  last_name: Matsunami
- first_name: Tsunehiro
  full_name: Takeuchi, Tsunehiro
  last_name: Takeuchi
citation:
  ama: Sato K, Singh S, Yamazaki I, et al. Improvement of thermoelectric performance
    of flexible compound Ag2S0.55Se0.45 by means of partial V-substitution for Ag.
    <i>AIP Advances</i>. 2023;13(12). doi:<a href="https://doi.org/10.1063/5.0171888">10.1063/5.0171888</a>
  apa: Sato, K., Singh, S., Yamazaki, I., Hirata, K., Ang, A. K. R., Matsunami, M.,
    &#38; Takeuchi, T. (2023). Improvement of thermoelectric performance of flexible
    compound Ag2S0.55Se0.45 by means of partial V-substitution for Ag. <i>AIP Advances</i>.
    AIP Publishing. <a href="https://doi.org/10.1063/5.0171888">https://doi.org/10.1063/5.0171888</a>
  chicago: Sato, Kosuke, Saurabh Singh, Itsuki Yamazaki, Keisuke Hirata, Artoni Kevin
    R. Ang, Masaharu Matsunami, and Tsunehiro Takeuchi. “Improvement of Thermoelectric
    Performance of Flexible Compound Ag2S0.55Se0.45 by Means of Partial V-Substitution
    for Ag.” <i>AIP Advances</i>. AIP Publishing, 2023. <a href="https://doi.org/10.1063/5.0171888">https://doi.org/10.1063/5.0171888</a>.
  ieee: K. Sato <i>et al.</i>, “Improvement of thermoelectric performance of flexible
    compound Ag2S0.55Se0.45 by means of partial V-substitution for Ag,” <i>AIP Advances</i>,
    vol. 13, no. 12. AIP Publishing, 2023.
  ista: Sato K, Singh S, Yamazaki I, Hirata K, Ang AKR, Matsunami M, Takeuchi T. 2023.
    Improvement of thermoelectric performance of flexible compound Ag2S0.55Se0.45
    by means of partial V-substitution for Ag. AIP Advances. 13(12), 125206.
  mla: Sato, Kosuke, et al. “Improvement of Thermoelectric Performance of Flexible
    Compound Ag2S0.55Se0.45 by Means of Partial V-Substitution for Ag.” <i>AIP Advances</i>,
    vol. 13, no. 12, 125206, AIP Publishing, 2023, doi:<a href="https://doi.org/10.1063/5.0171888">10.1063/5.0171888</a>.
  short: K. Sato, S. Singh, I. Yamazaki, K. Hirata, A.K.R. Ang, M. Matsunami, T. Takeuchi,
    AIP Advances 13 (2023).
date_created: 2024-01-10T09:26:08Z
date_published: 2023-12-01T00:00:00Z
date_updated: 2024-01-10T13:49:09Z
day: '01'
ddc:
- '540'
department:
- _id: MaIb
doi: 10.1063/5.0171888
external_id:
  isi:
  - '001114917200005'
file:
- access_level: open_access
  checksum: a7098388b8ff822b47f5ddd37ed3bdbc
  content_type: application/pdf
  creator: dernst
  date_created: 2024-01-10T13:47:31Z
  date_updated: 2024-01-10T13:47:31Z
  file_id: '14792'
  file_name: 2023_AIPAdvances_Sato.pdf
  file_size: 9676071
  relation: main_file
  success: 1
file_date_updated: 2024-01-10T13:47:31Z
has_accepted_license: '1'
intvolume: '        13'
isi: 1
issue: '12'
keyword:
- General Physics and Astronomy
language:
- iso: eng
month: '12'
oa: 1
oa_version: Published Version
publication: AIP Advances
publication_identifier:
  eissn:
  - 2158-3226
publication_status: published
publisher: AIP Publishing
quality_controlled: '1'
status: public
title: Improvement of thermoelectric performance of flexible compound Ag2S0.55Se0.45
  by means of partial V-substitution for Ag
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 13
year: '2023'
...