Coating-Integrated Joule Heating Architecture for Energy-Efficient Hydrogen Release from Chemical Carriers

Hydrogen carriers offer a practical route to store and transport renewable electricity in chemical form, but the end-to-end efficiency of carrier-based hydrogen supply is often dictated by the terminal hydrogen-release step, where endothermic chemistry and nonproductive heat losses impose a substantial energy penalty. Here we present a coating-integrated Joule heating architecture that improves how energy is coupled into hydrogen-release reactors. A porous silicon carbide skeleton functions as a universal electrothermal converter, while the reaction-required catalyst is directly coated onto the silicon carbide surface, decoupling electrothermal heat generation from catalytic function yet preserving microscale thermal coupling at the active interface. This design removes the constraint of catalyst-bed conductivity and thereby generalizes Joule heating to diverse hydrogen-release chemistries. For ammonia decomposition driven by Joule heating, the Ru/CeO₂-coated silicon carbide reactor delivers a hydrogen production rate of 5.6 mol_H2 g_cat^-1 h^-1 at an input power of 23.4 W, with an energy consumption of 15.5 kWh kg_H2^-1. Using Pt/CeO₂ as the catalyst coating, the same platform is extended to liquid organic hydrogen carrier dehydrogenation, achieving 86.6% cyclohexane conversion at a power input of only 5.5 W─a performance comparable to that achieved by conventional thermal catalysis at 280 °C. Thermal profiling reveals the thermal state of the porous silicon carbide skeleton under Joule heating, captures gas-temperature evolution from inlet to outlet, quantifies energy flow distribution, and provides a theoretical basis for array-scale reactor design. This coating-integrated electrothermal platform is compatible and scalable, offering a general approach to energy-efficient hydrogen release from ammonia and other hydrogen carriers.