@misc{10481/106646,
year = {2025},
month = {9},
url = {https://hdl.handle.net/10481/106646},
abstract = {This study investigates the enhancement of energy storage capabilities in commercial carbon felts for vanadium
redox flow batteries (VRFBs) by strategically synthesizing and modifying metal-organic frameworks (ZIFs) with
Fe, Co, Ni, Cu, and Zn metal centers. ZIFs were hydrothermally synthesized and then thermally treated at 450 ◦C
(in an oxygen atmosphere) and 900 ◦C (in an inert nitrogen atmosphere). Thermally treated MOFs provide
several advantages as electrodes, including enhanced stability within the aggressive VRFB environment, larger
porosity, and optimized electrical conductivity. The resulting materials were characterized using scanning
electron microscopy (SEM), X-ray diffraction (XRD), inductively coupled plasma spectroscopy (ICP), and cyclic
voltammetry (CV) in three-electrode cells, providing detailed insights into their properties. The incorporation of
ZIF-derived materials provided suitable electrochemical kinetics for catalyzing VRFB reactions, as determined by
Tafel analysis. Upon identifying materials that exhibit superior electrochemical performance for use as both
positive and negative electrodes in a VRFB, these were incorporated into a two-electrode flow cell configuration
and compared with a cell assembled using unmodified commercial carbon felt. Electrochemical evaluation
revealed significant performance improvements with Zn-modified electrodes, particularly at high current densities. For example, energy efficiency increased from 5 % to 13 % (50–500 mA/cm2
), and accessible capacity
improved from 5 % (50 mA/cm2
) to 50 % (500 mA/cm2
), attributed to reduced polarization losses. Likewise, the
battery maintained a high coulombic efficiency for 500 cycles. Electrochemical impedance spectroscopy (EIS)
further confirmed lower resistive contributions and enhanced electrode-electrolyte interaction, validating ZIF
modification as a viable strategy for optimizing VRFB performance.},
organization = {MCIN/AEI/10.13039/501100011033 - European Union, Next-GenerationEU (PTI-TRANSENER project)},
organization = {Ministerio de Universidades of the Government of Spain (FPU20/04400)},
publisher = {Elsevier},
keywords = {Vanadium redox flow batteries},
keywords = {Carbon electrode},
keywords = {Energy storage},
title = {Enhanced electrochemical performance of vanadium redox flow battery electrodes via thermally treated MOF-carbon felt composites},
doi = {10.1016/j.est.2025.118260},
author = {Lobato-Peralta, Diego R. and Molina Serrano, Antonio J. and Luque Centeno, José M. and Sebastián, David and Carrasco Marín, Francisco and Lázaro, María J. and Alegre, Cinthia},
}