Peptide-Assembly-Assisted Triplet-Triplet Annihilation Photon Upconversion in Non-deoxygenated Water

Triplet annihilation upconversion (TTA-UC) has a great potential to many fields. However, a stable TTA-UC system with adjustable UC efficiency in non-deoxygenated water is still in urgent demand. Here, the first example of short peptide tuned UC luminescence in water is reported. With only a small amount of peptide, UC chromophores could assemble into tetrahedral nanorods with adjustable size and UC efficiency. Successful TTA-UC luminescence of these nanorods in water is achieved due to the regular and dense organization of molecular upconversion chromophores tuned by peptide, which facilitates triplet excitons migration, avoids aggregation induced quenching and screens molecular oxygen to upconversion chromophores.