All‐Vanadium Redox Flow Battery Electrodes Enhanced with Nanomaterial Catalysts via Binder‐Free Electrophoretic Deposition

Abstract Two‐dimensional nano catalysts including graphene, reduced graphene oxide (rGO), MXene and exfoliated MXene (Exf. MXene) were synthesized and compared with commercial multiwalled carbon nanotubes (CNTs) for use in all‐vanadium redox flow batteries (VRFBs). These catalytic materials were coated onto carbon cloth (CC) and carbon paper (CP) electrodes via a horizontal binder‐free electrophoretic deposition (EPD) process. Amongst all samples, CNT‐modified CC exhibited the highest electrocatalytic activity, with improved redox kinetics and reduced charge transfer resistance, as confirmed by cyclic voltammetry and impedance spectroscopy. When tested in a flow cell at 100 mA cm −2 , CNT‐functionalized CC electrodes delivered ∼20% higher energy efficiency and electrolyte utilization for 200 cycles compared to pristine CC. The superior performance is attributed to the porous, conductive CNT network enabling facile electron transport. These results establish CNTs as highly effective VRFB catalysts and demonstrate EPD's promise as a scalable strategy for advanced electrode fabrication.