Scalable Synthesis of Binder-free Carbon Fiber Electrode for Hydrogen Evolution Reaction

Abstract

Crafting cost-effective electrocatalytic electrodes that are both efficient and durable is a key hurdle in the quest for advanced energy conversion solutions. With the depletion of fossil fuels and escalating environmental concerns, hydrogen emerges as a promising alternative energy carrier. Electrocatalytic water splitting, a sustainable method for the hydrogen evolution reaction (HER) without pollutant emissions, has garnered substantial interest. Electrocatalytic water splitting, a sustainable method for the hydrogen evolution reaction (HER) without pollutant emissions, has garnered substantial interest. Typically, water electrolysis catalysts are synthesized as carbon-metal nanocomposite powders and coated onto electrodes using polymeric binders like Nafion™ or polytetrafluoroethylene. This method, however, tends to obscure the catalytic active sites needed for the reaction, hinder electron and mass transport, and cause uncontrolled microstructural degradation, creating large inert volumes, multiphase reactions with gas bubbles, and suboptimal interfaces for electron transfer. These issues can create inactive areas, complicate reactions with gas bubbles, and weaken the connections needed for electron transfer. Beyond electrocatalytic efficiency, stability presents a crucial challenge. The inherent weak adhesion of the approach leads to the detachment of coated materials under continuous gas evolution reactions and hydrogen bombardment when high current densities are applied repetitively, shortening the electrode's lifespan. Despite these hurdles, preparing catalysts for extensive application areas remains a challenge. This work introduces a method leveraging traditional carbon fiber synthesis to produce self-supported electrocatalysts. In addition, the internal structure of fibers intertwined with metal has been investigated to elucidate the relationship between catalytic activity and microstructure.