Speaker: Dr. Kingshuk Roy
TCG Crest, Kolkata
Title: “Realization, Quantification and Mitigation of
Hydrogen Evolution for Aqueous Zinc Metal Batteries”.
Day and Date: Friday, August 02, 2024
Time: 11.00 am.
Venue: Room no. 350, Chemistry Department
Second floor, Annex
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Hosted by Prof. Srinivasan Ramakrishnan
Abstract Aqueous Zinc (Zn) metal batteries (AZMBs) offer significant
advantages, including high specific capacity, low redox potential,
cost-effectiveness, and enhanced safety. However, their practical
deployment is hindered by challenges such as the hydrogen evolution
reaction (HER), Zn substrate corrosion, and dendrite growth, which
collectively degrade battery performance and cyclability. This talk will
present our recent advancements in addressing these critical issues. We
employed in-situ electrochemical mass spectrometry (ECMS), scanning
electrochemical microscopy (SECM) to quantitatively monitor HER during Zn
electrodeposition, discovering that even a small fraction of HER (0.3%)
significantly impacts long-term battery performance. Our investigation
revealed a strong correlation between HER and the porous morphology of
electrodeposited Zn, highlighting the detrimental effects of trapped H2 and
Zn corrosion during charging. To mitigate these challenges, we also
developed a novel additive that effectively alters the Zn2+ solvation
matrix and disrupts the hydrogen bond network of free water. This additive
significantly suppresses HER and dendrite formation, resulting in a 25-fold
improvement in cycle life. Comprehensive characterization techniques,
including nuclear magnetic resonance spectroscopy, high-resolution mass
spectrometry, density functional theory studies, X-ray diffraction, and
X-ray photoelectron spectroscopy, confirmed the formation of ion-conductive
SEI components and uniform Zn growth. Overall, this talk will provide
crucial insights into HER mechanisms and pave the way for designing more
stable and efficient AZMBs, thereby advancing the development of
next-generation energy storage technologies.
*Bio:* Dr. Kingshuk Roy is an assistant professor in the field of energy
storage at the Research Institute for Sustainable Energy (RISE), TCG CREST,
Kolkata. He specializes in the fundamental and interfacial electrochemistry
for next-generation energy storage devices. Prior to his current position,
Kingshuk conducted postdoctoral research under the guidance of Prof.
Jeffrey E. Dick at Purdue University, where he focused on fundamental
electrochemistry and kinetic measurements for various electrochemical
energy storage systems. Kingshuk has extensive experience in the design,
synthesis, and characterization of materials for battery applications,
resulting in over 20 high-impact journal publications and two international
patents. His exceptional research contributions earned him the "Outstanding
Young Scientist" award at Purdue University. At RISE, TCG CREST, Dr. Roy's
research group will concentrate on developing electrolyte additives,
co-solvents, and diluents and understanding interfaces and interphases for
next-generation aqueous and non-aqueous metal batteries, advancing the
development of innovative energy storage solutions.