Electrochemical CO2 Reduction - PowerPoint PPT Presentation
Title:
Electrochemical CO2 Reduction
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Electrochemical CO2 reduction reaction (eCO2RR) is performed on two intermetallic compounds formed by copper and gallium metals (CuGa2 and Cu9Ga4). Among them, CuGa2 selectively converts CO2 to methanol with remarkable Faradaic efficiency of 77.26% at an extremely low potential of −0.3 V vs RHE. The high performance of CuGa2 compared to Cu9Ga4 is driven by its unique 2D structure, which retains surface and subsurface oxide species (Ga2O3) even in the reduction atmosphere. The Ga2O3 species is mapped by X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS) techniques and electrochemical measurements. – PowerPoint PPT presentation
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Title: Electrochemical CO2 Reduction
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Structure-Tailored Surface Oxide on Cu-Ga
Intermetallics Enhances CO2 Reduction Selectivity
to Methanol at Ultra-Low Potential
Debabrata Bagchi Supervisor Prof. Sebastian C.
Peter 16th JNC Research Conference on Chemistry
of Materials (22/10/2022)
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Climate Challenge
The HadCRUT4 data set, 2014
climate.nasa.gov
Geoscientific model development discussions, 2016
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Electrochemical CO2 Reduction Reaction (ECO2RR)
Prof. T. Sargent, University of Toronto
Competing hydrogen evolution reaction
Joule 2018, 2, 825-832
Bagchi, D. Roy, S. Sarma S. C. and Peter, S.
C., Adv. Funct. Mater. 2022, 2209023 (Review)
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Limitation of Conventional Liquid phase ECO2RR
Cathode CO2 m(H e-) CxHyOz H2O
Anode 2H2O O2 4(H e-)
e-
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Gas phase ECO2RR in Flow cell
Flow Cell
Gas phase
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Bagchi, D. Sarkar, S. Singh, A. K. Vinod,
C. P. Peter, S. C., ACS Nano 2022, 16, 4,
61856196
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Gas Diffusion Electrode for Higher Current
Liq. products
Gas products
PTFE-based
Carbon-based
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Top-Down approach of Cu-Ga Intermetallic Synthesis
High-temperature synthesis
Cu-Ga phase diagram
Ball milling process for bulk to nano
SampleVulcan (21) 30 cycle, 15 min for each
cycle _at_ 500 rpm
J. Phase Equilib. Diff. 2016, 37, 350-362
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Structure of Cu-Ga Intermetallic Catalyst
CuGa2
Cu9Ga4
Space Group P4/mmm
CuGa2 has pseudo 2D-type structure promoting
more active surface
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Characterizations of Cu-Ga Intermetallic Catalyst
CuGa2
Cu9Ga4
CuGa2
CuGa2
Cu9Ga4
Cu9Ga4
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ECO2RR performance and Faradaic Efficiency
LSV
CuGa2
Cu9Ga4
Higher methanol selectivity on CuGa2
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Achieving Higher Current Density in Flow Cell
LSV
CuGa2
CuGa2
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Local Surface Electronic Structure Analysis
XPS Study
XAS Study
XAS was performed at PETRA III, beamline P64,
DESY, Germany
XPS was performed at NCL, Pune in the
collaboration with Dr. C. P. Vinod
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Probing Active Site In-Situ XAS Study
In-Situ
Ex-Situ
In-Situ Setup
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Bagchi, D. Roy, S. Dheer, L. Sarma, S. C.
Rajaji, V. Narayana, C. Waghmare, U. V.
Peter, S. C., Appl. Catal. B, 2021, 298, 20560
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In-Situ XAS study
Surface Gallium Oxide
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XAS was performed at PETRA III, beamline P64,
DESY, Germany
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In-Situ IR Experiment
In-Situ setup
ACS Energy Lett. 2019, 4, 682-689
Catal. Lett. 2005, 103, 83-88
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Summary
Activity
Active site
Selectivity
Mechanism
Stability
Higher rate
Bagchi, D. Raj, J. Singh, A. K. Cherevotan,
A. Roy, S. Manoj, K. S. Vinod, C. P. C.
Peter, S., Adv. Mater. 2022, 34, 2109426
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Thank you
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