title: Graphite felt modified with bismuth nanoparticles as negative electrode in a vanadium redox flow battery.
abstract: A graphite felt decorated with bismuth nanoparticles was studied as negative electrode in a vanadium redox flow battery (VRFB). The results confirm the excellent electrochemical performance of the bismuth modified electrode in terms of the reversibility of the V(3+) /V(2+) redox reactions and its long-term cycling performance. Moreover a mechanism that explains the role that Bi nanoparticles play in the redox reactions in this negative half-cell is proposed. Bi nanoparticles favor the formation of BiHx , an intermediate that reduces V(3+) to V(2+) and, therefore, inhibits the competitive irreversible reaction of hydrogen formation (responsible for the commonly observed loss of Coulombic efficiency of VRFBs). Thus, the total charge consumed during the cathodic sweep in this electrode is used to reduce V(3+) to V(2+) , resulting in a highly reversible and efficient process.
authors: Chemistry of Materials Department, Instituto Nacional del Carbón (INCAR-CSIC), Apdo. 73, 33080 Oviedo (Spain).
authors: David J
authors: DJ
authors: Suárez
authors: Zoraida
authors: Z
authors: González
authors: Clara
authors: C
authors: Blanco
authors: Marcos
authors: M
authors: Granda
authors: Rosa
authors: R
authors: Menéndez
authors: Ricardo
authors: R
authors: Santamaría
mesh_terms: D001729:Bismuth / Q000737:chemistry*; D011211:Electric Power Supplies; D004563:Electrochemistry; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D010084:Oxidation-Reduction; D013784:Textiles; D014639:Vanadium / Q000737:chemistry*
chemical_list: D014639:Vanadium; D006108:Graphite; D001729:Bismuth
keywords: bismuth; cyclic voltammetry; nanoparticles; redox flow battery; vanadium