PO-T2T；≥99% (HPLC)

Device configuration:
ITO/MoO₃ (3 nm)/ TAPC (35 nm)/CBP:TTM-3NCz (3.0 wt%; (40 nm) and CBP:TTM3PCz (3.0 wt%; 25 nm)/B3PYMPM (10 nm)/PO-T2T (70 nm)/LiF (0.8 nm)/Al (100 nm).

The first Tandem, All-exciplex-based WOLED was constructed using PO-T2T for a device structure configured by two parallel blend layers of mCP/PO-T2T and DTAF/PO-T2T, generating blue and yellow exciplex emission, respectively. The resulting device demonstrates for the first time a tandem, all-exciplex-based white-light OLED (WOLED) with excellent efficiencies ηext: 11.6%, ηc: 27.7 cd/A, and ηp: 15.8 ml/W with CIE(0.29, 0.35) and CRI 70.6 that are nearly independent of EL intensity. The tandem architecture and blend-layer donor/acceptor (1:1) configuration are two key elements that fully utilize the exciplex delay fluorescence, providing a paragon for the use of low-cost, abundant organic compounds en route to commercial WOLEDs.

PO-T2T is an electron transport/hole blocking material in OLED, or an electron acceptor material in organic electronics.

An efficient action of radical-based OLEDs, whose emission originates from a spin doublet, rather than a singlet or triplet exciton was demonstrated in a study published in Nature.
While the emission process is still spin-allowed in these OLEDs, the efficiency limitations imposed by triplet excitons are circumvented for doublets. Using a luminescent radical emitter, an OLED with maximum external quantum efficiency of 27% at a wavelength of 710nm-the highest reported value for deep-red and infrared LEDs was achieved. In this very efficient OLEDs, selective hole injection into the HOMO and electron injection to the SOMO was achieved imploying TAPC as the hole transport layer, and PO-T2T as the electron transport layer to form the fluorescent doublet excited state with near-unity internal quantum efficiency.