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A series of Zr–Al-MWW zeolites with different Zr state and layer-stacking structure are successfully synthesized via direct grafting zirconocene dichloride onto the external silanols of three kinds of MWW zeolites, i.e. MCM-22 with multilayered structure, ITQ-2 (through layer delaminated route) and OL-MWW (by direct hydrothermal synthesis) with oligolayered structure. The structure, porosity and state of grafted Zr species are distinctly different among the three Zr–Al-MWW zeolites. Zr-OL-MWW possesses the highest content of single Zr atoms with an ideal micro-meso-macro pore system, while Zr-MCM-22 and Zr-ITQ-2 contain two kinds of Zr species (ZrO 2 clusters and single Zr atoms) coexisting in various proportions. The high dispersion of single Zr atoms on OL-MWW can be assigned to the large amount of external silanols of OL-MWW. The as-prepared three bi-functional Zr–Al-MWW zeolites are used for the cascade Meerwein-Ponndorf-Verley (MPV) reduction and etherification (ETH) reaction. Among them, Zr-OL-MWW shows dramatically higher conversion of cinnamaldehyde and yield of 1-cinnamyl 2-propyl ether than Zr-MCM-22 and Zr-ITQ-2, owing to the higher catalytic activity of Lewis acid centers from single Zr atoms, as well as more integrated framework Al sites as Brønsted acid centers with good accessibility. This study offers a simple and efficient strategy to construct Lewis-Brønsted acidic zeolites with exposed heteroatom sites and integrated framework structure, which will provide especial potential in the catalytic conversion of macromolecules. Bi-functional Zr–Al-MWW zeolites, i.e. Zr-MCM-22, Zr-ITQ-2 and Zr-OL-MWW were synthesized by direct grafting of zirconocene dichloride onto the external silanols of three zeolite matrixes, and applied in the Lewis-Brønsted cascade reaction. [Display omitted] • Bi-functional Zr–Al-MWW zeolites were synthesized by a direct grafting strategy. • Zr site state correlated to the matching between the amount of external silanols and the content of grafted Zr species. • Oligolayered MWW nanosheet with abundant external silanols produced more single Zr sites than multilayered MWW zeolite. • The ideal hierarchical porosity, integrated Al sites and exposed singe Zr sites provided superior catalytic performance. [ABSTRACT FROM AUTHOR]