Flexible PET/Carbon/NiFe-LDH Electrode for Oxygen Evolution Reaction in Water-Splitting

Abstract

The development of low-cost, readily scalable catalytic systems for green hydrogen production is crucial for diverse research and industrial applications. This work demonstrates the facile coupling of carbon/NiFe-layered double hydroxide (LDH) onto flexible polyethylene terephthalate (PET) substrates deposited by blade coating and spray coating techniques. These low-temperature solution processes enable high-throughput electrode fabrication. The resulting carbon electrode exhibits sheet resistance of 25 Ω sq⁻¹, comparable to other state-of-the-art works, and displays excellent adhesion to the substrate and catalyst layer, thereby ensuring system stability. Remarkably, the developed electrode exhibits high catalytic activity for the oxygen evolution reaction (OER), achieving an overpotential of 215.9 and 267.4 mV at 10 mA cm⁻² in rigid and flexible substrates respectively, and maintaining its performance even at 10 mA cm⁻² for 24 h. This work highlights the potential of this methodology for producing readily transportable, flexible electrocatalytic systems with exceptional performance and minimal surface treatment of the substrate. Additionally, the use of low-cost, readily recyclable PET plastic aligns with the principles of circular economy, promoting the integration of this platform into both research and industrial environments.