Double-layered core–shell heterostructures of mSiO2@CdS@CeO2 abrasive systems toward photochemical mechanical polishing (PCMP) applications

•mSiO2@CdS@CeO2 heterostructures were developed toward PCMP as novel abrasive systems.•The ternary composites were composed of mesoporous cores and double-layered shells.•The novel abrasives afforded atomically planarized wafers with sub-nanoscale finish.•The involved CdS–CeO2 heterojunction contributed to an enhanced removal rate in PCMP.•The exact roles of the components of mSiO2@CdS@CeO2 system during PCMP were proposed.