Non-thermal Plasma Synergizes High-Alkalinity Hydroxyapatite Supported RhFe Bimetallic Catalyst for Direct Catalytic Decomposition of N₂O at Low Temperature

Hydroxyapatite (HAP) supported Rh, Fe, and Rh-Fe catalysts were prepared by impregnation, and the synergy effects between the catalyst and NTP (non-thermal plasma) on N₂O catalytic decomposition were also investigated. CO₂-TPD results show that HAP synthesized at high pH have a greater number of surface alkaline sites and promoted the adsorption of N₂O. RhFe/HAP-11 catalyst exhibited 95.9% activity for the direct catalytic decomposition of N₂O at 350 °C. Combining NTP with the RhFe/HAP-11 catalyst can significantly enhance the catalytic decomposition of N₂O and greatly reduce the reaction temperature. The one-stage combination method enables the radicals generated by the plasma to participate in the reaction immediately on the catalyst surface, so it is more conducive to the N₂O catalytic decomposition in the range of 150–200 °C. When NTP is applied, N₂O conversion on RhFe/HAP-11 at 200 °C increases a lot from 7.1 to 90.0%. Graphical Abstract: [Figure not available: see fulltext.]