Abstract
Through the optimization of synthesis conditions, we obtained large Cu-3(BTC)(2) crystals with a diameter of 2-4 mm. Such large crystals could be utilized as "chromatographic columns" for effective separation of organic dyes such as thionine (TH) and pyronin B (PB). It was found that the concentration of hydron was the key factor to obtain the large pure crystals. This strategy could be used to grow other hydrophilic MOFs.