“Electrodeposited Ni-Fe-TiO2 Alloy Composites as a Bifunctional Electrocatalyst for Alkaline Water Splitting Reactions”
Sreenivasan Annadurai
Abstract
The hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) that governs electrolytic water splitting are of interest as a way to store energy from renewable sources. However, replacing noble metal electrocatalyst with those comprised of lower cost, earth abundant elements remains a challenge as these materials impart a higher overpotential, and hence energy requirement, to both reactions. Guided by the recognized enhanced activity of Ni-based
hydroxides in alkaline media, and known enhancements of TiO2 in Co-Mo alloys for HER, the examination of Ni-Fe-TiO2 alloy composite electrocatalysts are explored.
Nano-scale TiO2 particles were embedded into Ni-Fe alloys by using galvanic and pulse-reverse electrodeposition, onto rotating cylinder electrodes. Pulse-reverse electrodeposition considerably increased the concentration of the particles incorporated into the alloy. The composition and morphology was characterized by x-ray fluorescence (XRF) spectroscopy and scanning electron microscopy (SEM), respectively. The addition of particles to the electrolyte affected both the deposit composition and morphology. The alloy composites were then used as electrocatalysts in 1 M KOH to characterize HER and OER via linear sweep voltammetry on the resulting hydroxide surface. The surface area was examined in a ferri/ferrocyanide electrolyte. The polarization data in 1 M KOH shows a significant reduction in the HER
overpotential when TiO2 particles are present in the Ni-Fe deposit. The surface analysis of Ni-Fe and Ni-Fe- TiO2 confirmed that the improvement in HER activity is not due to surface roughness but an intrinsic one. The OER rate was not significantly altered by the included TiO2 particles in the deposit. The stability of the electrocatalysts under an electrolysis for HER and an independent electrolysis for OER was examined.
Friday, 04/18/2025 at 10.00 am
Camp 250
Sreenivasan Annadurai is a PhD student at Clarkson University. He has a B.Tech degree in Chemical and electrochemical Engineering from CSIR – Central Electrochemical Research Institute. Since August 2023, he has been conducting research on producing efficient electrocatalysts for hydrogen evolution reactions using the electrodeposition technique under Prof. Elizabeth Podlaha-Murphy.