Efficient photoluminescence from the encumbered platinum(II) porphyrins

Completely enclosed platinum(II) porphyrins exhibit the dramatic improvements in photoluminescence properties since the intermolecular π–π interactions and intramolecular vibrations are effectively suppressed by the encapsulating and steric effect of peripheral bulky and saturated substituents. The absolute photoluminescence quantum yields (PLQY) is up to 0.46–0.55 and significantly improved over their parent PtTPP.