Perovskite luminescent crystal composition comprising perovskite luminescent crystals bearing a polymeric surface ligand having a molecular weight of at least 700 g/mol, wherein the polymeric surface ligand is a polymer comprising a backbone and side chains, wherein at least one side chain comprises at least one functional group selected from amines, carboxylates, phosphates, thiols or combinations thereof, wherein the binding of the perovskite luminescent crystals to the surface ligand occurs through the surface ligand's functional groups, thereby forming a perovskite luminescent crystal-ligand complex, and wherein the perovskite luminescent crystal-ligand complex is embedded in a polymer.