Perimeter‐intensified inverse Zr‐Co oxygen carrier for biomass chemical‐looping gasification with high CO selectivity

Abstract Chemical‐looping gasification (CLG) offers a promising route for renewable biomass valorization, yet conventional oxygen carrier regeneration with O₂/H₂O is energy‐intensive and often produces low‐quality syngas. Here, we develop an inverse ZrO 2 /Co 3 O 4 oxygen carrier that enables selective biochar oxidation and efficient lattice‐oxygen transfer for improved CLG performance. Under optimized conditions, the inverse CoZr‐75 achieves a gas yield of 21.96 mmol g biomass −1 with an H 2 /CO‐rich syngas and a lower heating value of 9.95 MJ m −3 , outperforming conventional counterparts and enhancing H₂ productivity by 242%. During regeneration, CO predominantly is generated via selective oxidation of residual carbon, indicating suppressed deep oxidation. Structural and operando analyses reveal a uniform Zr–O–Co interfacial architecture with enhanced reducibility and reversible redox cycling (Co 3 O 4 ⇌ CoO ⇌ Co 0 ), accounting for its stability and reactivity. These results demonstrate that inverse interfacial engineering provides an effective strategy for designing high‐performance oxygen carriers and advancing efficient, selective biomass‐to‐syngas conversion.