And to decipher the role of crystal facets in energy transfer, we have selected an organic dye, Rhodamine B as an acceptor, whose photophysical properties are well characterized. The reason for selection for these donors (D) -acceptor (A) pair is owing to nearly identical values of spectral overlap integral, J(λ) between emission of metal-doped PNCs (M:PNCs) and absorption of Rhodamine B (RhB).