화학공학소재연구정보센터
International Journal of Hydrogen Energy, Vol.45, No.3, 1890-1900, 2020
ZIF-8/PEDOT @ flexible carbon cloth electrode as highly efficient electrocatalyst for oxygen reduction reaction
Design and fabrication of highly efficient and low-cost oxygen reduction reaction (ORR) electrocatalysts is of paramount importance for practical applications. Herein, we proposed a cost-effective, metal-free catalyst based on ZIF-8 metal-organic framework nanoparticles/electro-polymerized poly(3,4-ethylenedioxythiophene) (PEDOT) film on the surface of flexible carbon cloth (CC) electrode (ZIF-8/PEDOT/CC) via a two-step procedure. For this purpose, worm-like PEDOT nanostructures were deposited on the surface of carbon fibers using a pulse electro-polymerization technique followed by facile growth of ZIF-8 polyhedra nanoparticles via a chemical bath deposition method. The ORR measurements in O-2-saturated KOH electrolyte solution using the modified CC electrode demonstrated that the prepared electrode exhibits remarkable electrocatalytic activity towards ORR with8 times increase in the cathodic current density compared to bare CC (J = 0.13-1.1 mA/cm(2)) along with lower overpotential due to the synergetic effects between ZIF-8 nanoparticles as particularly porous nanostructure act as electrolyte reservoirs and highly conductive PEDOT film. The Kouteckey-Levich analysis for the ZIF-8/PEDOT-modified CC electrode revealed that the oxygen reduction reaction proceeds via a nearly four-electron pathway along with superior tolerance to methanol crossover as well as enhanced stability in alkaline solution compared to the gold standard commercial Pt catalyst. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.