A confined MoN2@N-rich carbon catalyst derived from β-cyclodextrin encapsulating phosphomolybdic acid for oxidative removal of H2S.

[Display omitted] • A novel macrocycle-confinement pyrolysis strategy was proposed. • MoN 2 @NPC catalyst was first applied in heterogeneous removal systems for H 2 S. • Synergistic effect between MoN 2 and NPC promoted efficient desulfurization. • The durable removal and conversion of H 2 S can be maintained for >100 h. • The desulfurization product was proved as S 8. The efficient removal of H 2 S is significant to the chemical industry and environmental protection. In this study, a macrocycle-confinement pyrolysis strategy was explored to synthesize a confined MoN 2 @N-rich porous carbon (MoN 2 @NPC) catalyst using β-cyclodextrin encapsulating phosphomolybdic acid (PMo 12 ⊂ β-CD) as a Mo precursor to improve the desulfurization activity of carbonaceous catalysts for the efficient conversion of H 2 S to sulfur. The decomposition of PMo 12 ⊂ β-CD not only generated well distributed MoN 2 sites, but also enriched pore structures due to the pore-forming ability of β-CD. MoN 2 @NPC possessed a high breakthrough capacity of 173.9 mg/g at room temperature and excellent durability (>100 h) at 200 °C toward continuous H 2 S selective oxidation. Furthermore, MoN 2 @NPC showed a remarkable superiority to common catalysts (PC, NPC, and MoN 2 -NPC), revealing the effectiveness of the macrocycle-confinement pyrolysis strategy for strengthening desulfurization activity. The excellent desulfurization ability of MoN 2 @NPC was attributed to the synergetic effect of uniform MoN 2 sites and N species (pyridinic N and pyrrolic N). Additionally, the formed water film and activated O 2 on MoN 2 @NPC further induced H 2 S dissociation and oxidation. This work provides a key insight into the behavior of H 2 S oxidative removal over NPC-based catalysts and offers a promising route to construct non-precious catalysts with high desulfurization activity. [ABSTRACT FROM AUTHOR]