Unravelling the nature, evolution and spatial gradients of active species and active sites in the catalyst bed of unpromoted and K/Ba-promoted Cu/Al 2 O 3 during CO 2 capture-reduction

Space- and time-resolved operando DRIFTS, XAFS, and XRD uncovered the involved surface chemical species and active sites, especially the unique functions of K and Cu, during the CO 2 capture-reduction process.