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[Display omitted] • Calcined Ge-UTL encountered structural degradation under pure water solution at RT. • A simply ultrasonic treatment caused random arrangement of the formed cfi layers. • The stacking faults of cfi layers generated abundant intracrystal mesopores. • An excellent styrene epoxidation activity (TOF = 403 h−1) is achieved on Co-Meso-UTL. Co-zeolites with hierarchical porous are significantly desirable for the liquid-phase selective epoxidation of styrene that required relatively open reaction spaces. A typical UTL germanosilicate with the absence of organic structure-directing agent molecules inside pore channels suffered from severe structural collapse after ultrasonic treatment under pure water medium, originating from the unstable germanium-rich double four ring subunits. The simple strategy cleaved the weak linkage Ge-O bands and caused the irregular location of silicon-rich cfi layers. Subsequently, Co activity centers was incorporated into the framework through reacting with the abundant silanol groups located in the hydroxyl nests at room temperature. The random arrangement of mono- or multi- cfi layers induced the stacking faults and generated a large amount of intracrystal mesopores after calcination. The resultant Co-Meso-UTL catalysts favored the molecules diffusion of large-sized styrene and target products, improving the accessibility of Co active sites and exhibiting excellent catalytic performance in the styrene epoxidation reaction with single hydrogen peroxide (H 2 O 2) oxidant. Especially, high styrene oxide product selectivity was also obtained through controlling appropriate H 2 O 2 -added content as well as reaction time, which possessed a highest turnover frequency value of 403 h−1 among the reported catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Calcined *CTH experienced structural collapse and reconstruction by HNO3 treatment. • Sn-*CTH were post-synthesized via the structural rearrangement and Sn incorporation. • Sn-*CTH exhibited a high catalytic activity in the Baeyer-Villiger oxidation. • High ε-caprolactone selectivity was obtained through controlling reaction parameters. Germanium-rich *CTH zeolite without organic molecules located inside pore channels experienced only partial structural collapse and subsequently repaired to high-silica structure analogous to the original topology in a short time. The surprise acid-hydrolysis process has caused a large amount of framework Ge ions were removed, giving rise to abundant hydroxyl nests. Benefiting from the unexpected variation of framework structure and chemical composition, stannosilicates Sn-*CTH with extra-large pores and various Sn loadings (Si/Sn molar ratio in the range of 30-∞) were post-prepared depending on the reaction between the added (NH 4) 2 SnCl 6 species and the formed silanol groups in the hydroxyl nests. The resultant Sn-*CTH zeolites were able to release significantly the diffusion limitations encountered by the bulky substrates and oxidants, exhibiting promising activities to catalyze the Baeyer-Villiger (B-V) oxidation of ketones with single oxidant either hydrogen peroxide (H 2 O 2) or large-sized tert-butyl hydroperoxide (TBHP). Especially, high ε-caprolactone product selectivity was also obtained in the B-V oxidation of cyclohexanone using H 2 O 2 oxidant through reducing the H 2 O 2 /cyclohexanone molar ratio as well as controlling appropriate reaction time, which was more efficient than the traditional Sn-Beta-F catalyst. [ABSTRACT FROM AUTHOR]