Highly stable and air-resistant photonic upconversion organogels with self-healing and temperature responsiveness

Abstract

Effective triplet-triplet annihilation photon upconversion (TTA-UC) is usually difficult to achieve under aerobic conditions, but highly desirable for practical applications where durability is in great need to sustain environment loads...

Multi-wavelength excited triplet–triplet upconversion microcrystals based on hot-band excitation for optical information encryption

“…In this work, the multi-wavelength excited UC performance of PtOEP/DPA microcrystals, which are one of the most widely used TTA-UC dye pairs, based on hot-band excitation mode was systematically investigated. [26][27][28][29][30] In addition to the commonly used excitation wavelength of 532 nm, this TTA-UC microcrystalline system also achieved 443 nm blue UC emission under excitation at 589, 635, 655, and 671 nm, with a maximum anti-Stokes shift of 0.95 eV. Moreover, the maximum anti-Stokes shift in the solution can reach 1.04 eV.…”

“…As one of the most commonly used TTA-UC dye molecule pairs, PtOEP and DPA are still regarded as a classic model system and have been applied in various TTA-UC research studies. [26][27][28][29][30] However, when using selective excitation of the sensitizer PtOEP at 532 nm (zero vibrational energy level in the ground state, S 0 n 0 ), the resulting green-to-blue TTA-UC has a small anti-Stokes shift of 0.55 eV. To increase the anti-Stokes shift of TTA-UC, excitation of PtOEP at the hot-band vibrational energy levels in the ground state (S 0 n t ) was conducted using diode lasers of 589 nm, 635 nm, 655 nm and 671 nm, respectively.…”