Yellow
emission is a complementary color of blue for achieving
white emission. Here, we report two yellow-emitting PtAg2 heterotrinuclear complexes (1 and 2) of
4-ethynyl-N,N-diphenylaniline, supported
by bis(diphenylphosphinomethyl)phenylphosphine (dpmp) and bis(di-o-tolylphosphinomethyl)phenylphosphine (dTolmp), respectively.
The solution-processed organic light-emitting diode based on complex 1 exhibits yellow emission peaked at 567 nm with the highest
current efficiency (CE) of 49.7 cd A–1 and an external
quantum efficiency (EQE) of 14.3%. Remarkably, the device performance
of complex 2 containing dTolmp with a larger steric hindrance
as the supporting ligand is dramatically enhanced with the CE boosting
to 69.1 cd A–1 and EQE of 21.7% and, more importantly,
a better color saturation of yellow emission peaked at 579 nm with
the CIE of (0.49, 0.50).