Plasma-Driven Dual-Membrane System for Intensified Hydrogen Production with Integrated Ammonia Recovery

Ammonia (NH₃) is a principal carbon-free hydrogen (H₂) carrier, yet its decomposition via conventional thermocatalysis is restricted by kinetically demanding high temperatures. Integrating the reaction with in situ product removal to achieve high decomposition efficiency under mild conditions presents a formidable challenge. Here, we report a plasma-enhanced dual-membrane ammonia decomposition system (PEDMADS) that synergistically couples dielectric barrier discharge (DBD), a highly dispersed atomic layer deposition (ALD)-synthesized Ru/SiO₂ catalyst, and an integrated ultrathin Pd membrane (1.8 μm) to enable a high H₂ space-time yield of 1567 mmol g⁻¹ h⁻¹ at 400 °C. Furthermore, a downstream cascade of high-performance Silicalite-1 (S-1) membranes achieved energy-efficient NH₃ recovery, exhibiting unprecedented NH₃/H₂ and NH₃/N₂ separation factors of 686 and 7076 under ambient conditions. Molecular dynamics simulations revealed this selectivity arose from a preferential adsorption-driven molecular sieving mechanism. The five-stage cascade reduced the effluent NH₃ concentration from 24.1% to below 4%, achieving 87% removal efficiency. Techno-economic analysis indicated a levelized cost of 0.92 $/kg H₂ with a 95.9% carbon footprint reduction compared to the conventional thermal process, thus offering a compelling blueprint for a sustainable ammonia-hydrogen economy.