Enhancing plasma-assisted NH3 decomposition through zeolite topology and Si/Al ratio

Efficient low-temperature NH 3 decomposition remains challenging due to the stability of N–H bonds. In this work, we systematically investigate plasma-assisted NH 3 decomposition over zeolites with varying topologies (SSZ-13, ZSM-5, and Beta) and Si/Al ratios in a dielectric barrier discharge (DBD) reactor. Beta-25 exhibits superior performance, achieving 60.0% NH 3 conversion and 1.33 mol H2 /(g cat ·kWh) energy yield, which are 7.7% and 14.6% higher, respectively, than those of the plasma-only system. Electrical analysis and optical emission spectroscopy reveal that Beta-25 enhances micro-discharge behavior and high-energy electron generation, promoting radical formation. Temperature programmed desorption of NH 3 (NH 3 -TPD) and X-ray photoelectron spectroscopy (XPS) indicate that low Si/Al ratio facilitated NH 3 adsorption–desorption and accelerate nitrogen intermediate release. These findings highlight a synergy between zeolite topology, acidity, and plasma characteristics, offering insights for designing efficient zeolite-based catalysts for plasma-driven NH 3 decomposition and sustainable hydrogen production under mild conditions. • Plasma-assisted NH 3 decomposition is regulated by zeolite topology and Si/Al ratio. • Beta-25 exhibits the highest NH 3 conversion (60.0%) and H 2 energy yield (1.33 mol/(g ca t·kWh)). • The presence of Beta-25 enhances micro-discharge intensity and increases mean electron energy. • Beta-25 with moderate NH 3 adsorption strength accelerates NH 3 turnover in plasma reactor. • Synergy between plasma and Beta-25 enables efficient low-temperature hydrogen production.