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Chiral metal-organic frameworks have shown great potential in enantioselective separation and asymmetric catalysis due to their diverse and adjustable structures with abundant chiral recognition sites. Herein, a new chiral post-synthetic modification was used for preparing an achiral@chiral metal-organic frameworks core-shell composite [Cu 3 (Btc) 2 ]@[Cu 2 ((+)-Cam) 2 Dabco] by a superficial chiral etching method. The [Cu 3 (Btc) 2 ]@[Cu 2 ((+)-Cam) 2 Dabco] composite was utilized as a novel chiral stationary phase for HPLC enantioseparation. Various racemates were separated on the [Cu 3 (Btc) 2 ]@[Cu 2 ((+)-Cam) 2 Dabco]-packed column (column A). It exhibited good chiral resolving ability toward many different kinds of racemates, especially chiral drugs. Among them, the highest resolution value for 1,2-diphenyl-1,2-ethanediol reaches 2.70. The relative standard deviations of retention time and peak area for repeated separation of 1,2-diphenyl-1,2-ethanol were 0.45% and 0.81%, respectively. Compared with the resolution ability of [Cu 2 ((+)-Cam) 2 Dabco]-packed column (column B), column A shows higher column efficiency and better separation performance than those of column B. The results indicated that the [Cu 3 (Btc) 2 ]@[Cu 2 ((+)-Cam) 2 Dabco] as a stationary phase can greatly improve the column efficiency and chiral resolution ability of chiral metal-organic frameworks, which demonstrated that the superficial chiral etching as an economic and efficient strategy opens up a new way for the application of metal-organic frameworks.

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