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Many layered superlattice materials intrinsically possess large Seebeck coefficient and low lattice thermal conductivity,but poor electrical conductivity because of the interlayer transport barrier for charges,which has become a stumbling block for achieving high thermoelectric performance.Herein,taking BiCuSeO superlattice as an example,it is demonstrated that efficient interlayer charge release can increase carrier concentration,thereby activating multiple Fermi pockets through Bi/Cu dual vacancies and Pb codoping.Experimental results reveal that the extrinsic charges,which are introduced by Pb and initially trapped in the charge-reservoir[Bi2C2]2+sublayers,are effectively released into[Cu2Se2]2-sublayers via the channels bridged by Bi/Cu dual vacancies.This efficient interlayer charge release endows dual-vacancy-and Pb-codoped BiCuSeO with increased carrier concentration and electrical conductivity.Moreover,with increasing carrier concentration,the Fermi level is pushed down,activating multiple converged valence bands,which helps to maintain a relatively high Seebeck coefficient and yield an enhanced power factor.As a result,a high ZT value of~1.4 is achieved at 823 K in codoped Bi0.90Pb0.06Cu0.96SeO,which is superior to that of pristine BiCuSeO and solely doped samples.The present findings provide prospective insights into the exploration of high-performance thermoelectric materials and the underlying transport physics.