A one-pot method for encapsulation of dye, which can be applied for dye-sensitized solar cells (DSSCs), and synthesis of hierarchical porous zeolitic imidazolate frameworks (ZIF-8), is reported. The size of the encapsulated dye tunes the mesoporosity and surface area of ZIF-8. The mesopore size, Langmuir surface area and pore volume are 15 nm, 960–1500 m2 · g−1 and 0.36–0.61 cm3 · g−1, respectively. After encapsulation into ZIF-8, the dyes show longer emission lifetimes (greater than 4–8-fold) as compared to the corresponding non-encapsulated dyes, due to suppression of aggregation, and torsional motions.