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An ordered macro-microporous single-crystalline MOF with micron-sized hollow exhibits a recorded CrO 4 2- adsorption capacity of 609 mg/g, and offers the promising application for CrO 4 2- disposal in nuclear waste. [Display omitted] • A rarely hollow single-crystalline framework 1 with ordered macro-micropores. • MOF 1 possesses the record CrO 4 2- adsorption capacity of 609 mg/g. • MOF 1 can maintain its high CrO 4 2- adsorption capacity after 400 kGy β irradiation. • 1 offers the promising practical application for CrO 4 2- disposal. The vitrification process represents an effective method for high-level radioactive waste disposal, but CrO 4 2- can form crystalline spinels within the glass to cause the secondary leak of radioactive waste. Porous materials are widely used for trapping CrO 4 2-, but the unsatisfied adsorbing capacity and poor selectivity of reported materials make CrO 4 2- enrichment to be a challenging issue. Herein, a rarely hollow single-crystalline MOF (1) with ordered macro-micropores of 13 μm and 8.6 Å was obtained, exhibiting high N 2 adsorption of 339.2 cm3/g and large BET surface area of 1150 m2/g. Cooperation effect between microporous frameworks and micron-sized channels in crystals endows 1 with excellent chromate removal capacity of 609 mg/g, which is a record value known to date among the anion-exchange materials for CrO 4 2- removal. The kinetic analysis revealed that such adsorption was a pseudo-second-order adsorption process. Framework 1 possessed high pH stability and irradiation resistance, can repeatedly absorb/desorb CrO 4 2- to some degree. More importantly, sample 1 can maintain its high CrO 4 2- adsorption capacity after 400 kGy β irradiation, offering the promising application for CrO 4 2- disposal in high-level radioactive waste. [ABSTRACT FROM AUTHOR]