Overall water splitting on Ni-doped WC and MoC

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Mechanistic Insights into the Promotional Effect
of Ni Substitution in Non-noble Metal Carbides
for Highly Enhanced Water Splitting
Debabrata Bagchi (Oral Presentation No.
T10A38) Supervisor Prof. Sebastian C.
Peter JNCASR, Bangalore 3rd Indian Materials
Conclave and 32nd Annual General Meeting of MRSI
(23/12/2021)
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Global Outlook Hydrogen as an alternative Energy
Energy consumption TWh/y
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Electrochemical Water Splitting Catalyst for HER
OER
Low cost alternative catalyst ?
Oxygen Evolution
Hydrogen Evolution
Han, W. et al., Frontiers in Chemistry 2020, 8,
1025
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Catalyst Design Strategy Ni-WC/MoC_at_NGC
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Characterizations
XPS study
Powder XRD
Raman Spectra
Ni-doping from XRD shift
Oxidation state of W/Mo Ni from XPS
Defect in C matrix N-doping
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Microscopic Analysis
Ni-MoC_at_NGC
Ni-WC_at_NGC
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Hydrogen Evolution Reaction (HER) in 0.5M H2SO4
Hydrogen Evolution Reaction (HER) in 0.5M H2SO4
Hydrogen Evolution Reaction (HER) in 0.5 M H2SO4
Activity
Stability
Tafel Slope
Impedance
Chronoamperometric Stability
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Hydrogen Evolution Reaction (HER) in 0.5M H2SO4
Hydrogen Evolution Reaction (HER) in 0.5M H2SO4
HER in 0.5 M KOH
Activity
Stability
Tafel Slope
Ni-doping enhancing the activity of carbide
Chronoamperometric Stability
Impedance
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Hydrogen Evolution Reaction (HER) in 0.5M H2SO4
Hydrogen Evolution Reaction (HER) in 0.5M H2SO4
Oxygen Evolution Reaction (OER) in 0.5 M KOH
Stability
Activity
IrO2
Tafel Slope
Chronoamperometric Stability
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In-situ X-ray Absorption Spectroscopic Analysis
ECell set-up
Detector
X-ray source
Experiment was performed at PETRA III, beamline
P64, of DESY, Germany.
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1st Role of Ni HER in Acid
Ex-situ XAS
In-situ XAS
WC_at_NGC
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2nd Role of Ni OER in Base
Ni-Edge
3rd Role of Ni Dissolution and Site Vacancies
Computational Understanding
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Theoretical calculation was performed in
collaboration with Prof. Waghmare, JNCASR.
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Hydrogen Evolution Reaction (HER) in 0.5M H2SO4
Hydrogen Evolution Reaction (HER) in 0.5M H2SO4
Overall Water Splitting in 0.5M KOH
Correlation of overpotentials
Production of H2 O2
Stability
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Summary
Cathode
H2
Anode
I. F. -19.503
O2
0.5M KOH
D. Bagchi, S. Roy, L. Dheer, S. C. Sarma, V.
Rajaji, C. Narayana, U. V. Waghmare, S. C. Peter,
Appl. Catal. B, 2021, 298, 20560.
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Acknowledgement

• My supervisor, Prof. Sebastian C. Peter for his
  constant support and encouragement
• All my present and past lab members

Thank you