Morphological and Elemental Investigations on CoFeBO Thin Films Deposited by Pulsed Laser Deposition for Alkaline Water Oxidation: Charge Exchange Efficiency as the Prevailing Factor in Comparison with the Adsorption Process
Coatings; Electrocatalysis; Hierarchical; Nanostructured; Water oxidation
Abstract: Mixed transition-metals oxide electrocatalysts have shown huge potential for electrochemical water oxidation due to their earth abundance, low cost and excellent electrocatalytic activity. Here we present CoFeBO coatings as oxygen evolution catalyst synthesized by Pulsed Laser Deposition (PLD) which provided flexibility to investigate the effect of morphology and structural transformation on the catalytic activity. As an unusual behaviour, nanomorphology of 3D-urchin-like particles assembled with crystallized CoFe2O4 nanowires, acquiring high surface area, displayed inferior performance as compared to coreshell particles with partially crystalline shell containing boron. The best electrochemical activity towards water oxidation in alkaline medium with an overpotential of 315 mV at 10 mA/cm2 along with a Tafel slope of 31.5 mV/dec was recorded with coreshell particle morphology. Systematic comparison with control samples highlighted the role of all the elements, with Co being the active element, boron prevents the complete oxidation of Co to form Co3+ active species (CoOOH), while Fe assists in reducing Co3+ to Co2+ so that these species are regenerated in the successive cycles. Thorough observation of results also indicates that the activity of the active sites play a dominating role in determining the performance of the electrocatalyst over the number of adsorption sites. The synthesized CoFeBO coatings displayed good stability and recyclability thereby showcasing potential for industrial applications. Graphic Abstract: [Figure not available: see fulltext.] 2021, The Author(s).
Popat Y.; Orlandi M.; Gupta S.; Bazzanella N.; Pillai S.; Patel M.K.; Miotello A.; Patel N.
Catalysis Letters, Vol-152, No. 2, pp. 438-451.
All Open Access; Hybrid Gold Open Access
Popat Y., Department of Physics, Universitdegli Studi di Trento, Trento, Povo, 38123, Italy; Orlandi M., Department of Physics, Universitdegli Studi di Trento, Trento, Povo, 38123, Italy; Gupta S., School of Engineering, University of Liverpool, Liverpool, L69 3GH, United Kingdom; Bazzanella N., Department of Physics, Universitdegli Studi di Trento, Trento, Povo, 38123, Italy; Pillai S., Materials Science and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram, 695019, India; Patel M.K., School of Engineering, University of Liverpool, Liverpool, L69 3GH, United Kingdom; Miotello A., Department of Physics, Universitdegli Studi di Trento, Trento, Povo, 38123, Italy; Patel N., Department of Physics and Electronics, Christ University, Karnataka, Bengaluru, 560029, India