---
_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.
corr_author: '1'
date_created: 2024-01-17T12:48:35Z
date_published: 2024-01-08T00:00:00Z
date_updated: 2024-10-09T21:07:53Z
day: '08'
department:
- _id: MaIb
doi: 10.1021/acsaem.3c02519
external_id:
  isi:
  - '001138342900001'
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
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: '12227'
abstract:
- lang: eng
  text: Polydicyclopentadiene (pDCPD), a thermoset with excellent mechanical properties,
    has enormous potential as a lightweight, tough, and stable matrix material owing
    to its highly cross-linked macromolecular network. This work describes generating
    pDCPD-based foams and hierarchically porous carbons derived therefrom by combining
    ring-opening metathesis polymerization (ROMP) of DCPD, high internal phase emulsions
    (HIPEs) as structural templates, and subsequent carbonization. The structure and
    function of the carbon foams were characterized and discussed in detail using
    scanning electron, transmission electron, or atomic force microscopy (SEM, TEM,
    AFM), electron energy-loss spectroscopy (TEM-EELS), N2 sorption, and analyses
    of electrical conductivity as well as mechanical properties. The resulting materials
    exhibited uniform, shape-retaining shrinkage of only ∼1/3 after carbonization.
    No structural failure was observed even when the pDCPD precursor foams were heated
    to 1400 °C. Instead, the high porosity, void size, and 3D interconnectivity were
    fully preserved, and the void diameters could be adjusted between 87 and 2.5 μm.
    Moreover, foams have a carbon content >97%, an electronic conductivity of up to
    2800 S·m–1, a Young’s modulus of up to 2.1 GPa, and a specific surface area of
    up to 1200 m2·g–1. Surprisingly, the pDCPD foams were carbonized into shapes other
    than monoliths, such as 10’s of micron thick membranes or foamy coatings adhered
    to a metal foil or grid substrate. The latter coatings even adhere upon bending.
    Finally, as a use case, carbonized foams were applied as porous cathodes for Li–O2
    batteries where the foams show a favorable combination of porosity, active surface
    area, and pore size for outstanding capacity.
acknowledgement: S.K. acknowledges the financial support from the Slovenian Research
  Agency (grants P1-0021, P2-0150). Support by Graz University of Technology (LP-03
  – Porous Materials@Work) and from VARTA Innovation GmbH is kindly acknowledged.
  We thank Umicore for providing the initiator and Matjaž Mazaj (National Institute
  of Chemistry, Ljubljana) and Karel Jerabek (Czech Academy of Sciences) for measurements
  and fruitful discussions. S.A.F. is indebted to the Austrian Federal Ministry of
  Science, Research and Economy; the Austrian Research Promotion Agency (Grant No.
  845364); and ISTA for support.
article_processing_charge: No
article_type: original
author:
- first_name: Sebastijan
  full_name: Kovačič, Sebastijan
  last_name: Kovačič
- first_name: Bettina
  full_name: Schafzahl, Bettina
  last_name: Schafzahl
- first_name: Nadejda B.
  full_name: Matsko, Nadejda B.
  last_name: Matsko
- first_name: Katharina
  full_name: Gruber, Katharina
  last_name: Gruber
- first_name: Martin
  full_name: Schmuck, Martin
  last_name: Schmuck
- first_name: Stefan
  full_name: Koller, Stefan
  last_name: Koller
- first_name: Stefan Alexander
  full_name: Freunberger, Stefan Alexander
  id: A8CA28E6-CE23-11E9-AD2D-EC27E6697425
  last_name: Freunberger
  orcid: 0000-0003-2902-5319
- first_name: Christian
  full_name: Slugovc, Christian
  last_name: Slugovc
citation:
  ama: 'Kovačič S, Schafzahl B, Matsko NB, et al. Carbon foams via ring-opening metathesis
    polymerization of emulsion templates: A facile method to make carbon current collectors
    for battery applications. <i>ACS Applied Energy Materials</i>. 2022;5(11):14381-14390.
    doi:<a href="https://doi.org/10.1021/acsaem.2c02787">10.1021/acsaem.2c02787</a>'
  apa: 'Kovačič, S., Schafzahl, B., Matsko, N. B., Gruber, K., Schmuck, M., Koller,
    S., … Slugovc, C. (2022). Carbon foams via ring-opening metathesis polymerization
    of emulsion templates: A facile method to make carbon current collectors for battery
    applications. <i>ACS Applied Energy Materials</i>. American Chemical Society.
    <a href="https://doi.org/10.1021/acsaem.2c02787">https://doi.org/10.1021/acsaem.2c02787</a>'
  chicago: 'Kovačič, Sebastijan, Bettina Schafzahl, Nadejda B. Matsko, Katharina Gruber,
    Martin Schmuck, Stefan Koller, Stefan Alexander Freunberger, and Christian Slugovc.
    “Carbon Foams via Ring-Opening Metathesis Polymerization of Emulsion Templates:
    A Facile Method to Make Carbon Current Collectors for Battery Applications.” <i>ACS
    Applied Energy Materials</i>. American Chemical Society, 2022. <a href="https://doi.org/10.1021/acsaem.2c02787">https://doi.org/10.1021/acsaem.2c02787</a>.'
  ieee: 'S. Kovačič <i>et al.</i>, “Carbon foams via ring-opening metathesis polymerization
    of emulsion templates: A facile method to make carbon current collectors for battery
    applications,” <i>ACS Applied Energy Materials</i>, vol. 5, no. 11. American Chemical
    Society, pp. 14381–14390, 2022.'
  ista: 'Kovačič S, Schafzahl B, Matsko NB, Gruber K, Schmuck M, Koller S, Freunberger
    SA, Slugovc C. 2022. Carbon foams via ring-opening metathesis polymerization of
    emulsion templates: A facile method to make carbon current collectors for battery
    applications. ACS Applied Energy Materials. 5(11), 14381–14390.'
  mla: 'Kovačič, Sebastijan, et al. “Carbon Foams via Ring-Opening Metathesis Polymerization
    of Emulsion Templates: A Facile Method to Make Carbon Current Collectors for Battery
    Applications.” <i>ACS Applied Energy Materials</i>, vol. 5, no. 11, American Chemical
    Society, 2022, pp. 14381–90, doi:<a href="https://doi.org/10.1021/acsaem.2c02787">10.1021/acsaem.2c02787</a>.'
  short: S. Kovačič, B. Schafzahl, N.B. Matsko, K. Gruber, M. Schmuck, S. Koller,
    S.A. Freunberger, C. Slugovc, ACS Applied Energy Materials 5 (2022) 14381–14390.
corr_author: '1'
date_created: 2023-01-16T09:48:53Z
date_published: 2022-10-16T00:00:00Z
date_updated: 2024-10-09T21:03:48Z
day: '16'
ddc:
- '540'
department:
- _id: StFr
doi: 10.1021/acsaem.2c02787
external_id:
  isi:
  - '000875635900001'
file:
- access_level: open_access
  checksum: 572d15c250ab83d44f4e2c3aeb5f7388
  content_type: application/pdf
  creator: dernst
  date_created: 2023-01-27T09:09:15Z
  date_updated: 2023-01-27T09:09:15Z
  file_id: '12420'
  file_name: 2022_AppliedEnergyMaterials_Kovacic.pdf
  file_size: 13105589
  relation: main_file
  success: 1
file_date_updated: 2023-01-27T09:09:15Z
has_accepted_license: '1'
intvolume: '         5'
isi: 1
issue: '11'
keyword:
- Electrical and Electronic Engineering
- Materials Chemistry
- Electrochemistry
- Energy Engineering and Power Technology
- Chemical Engineering (miscellaneous)
language:
- iso: eng
license: https://creativecommons.org/licenses/by/4.0/
month: '10'
oa: 1
oa_version: Published Version
page: 14381-14390
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: 'Carbon foams via ring-opening metathesis polymerization of emulsion templates:
  A facile method to make carbon current collectors for battery applications'
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: 4359f0d1-fa6c-11eb-b949-802e58b17ae8
volume: 5
year: '2022'
...