Synthesis and Applications of Luminescent Materials Based on Various Organometallic Complexes

Abstract

A discrete heterodinuclear Al(III)/Ir(III) complex, $[(3,5-^tBu_2)salenAl(\mu u-hpbpy)Ir(ppy)_2]^+[PF_6]^-$ ($\Bf{1}$, Hhpbpy = 4´-(4-hydroxyphenyl)-6´-phenyl-2,2´-bipyridine) was prepared from the molecular coupling of a salen-based aluminum complex as a host and a phenylpyridine-based ionic iridium complex as a phosphorescent emitter. The complex shows bright orange light emission along with stable colour purity, low turn-on voltage, and good device performance when used as an active layer in host-dopant assembly OLEDs based on a solution process. (Device OLED-1 has a maximum brightness $(\It{L_{max}})$ of $1,002 cd m^{-2}$ at 10.8 V and a luminance efficiency $(\eta_L)$ of 1.8 cd $A^{-1}$, EQE of 0.94%, and a luminous efficiency (LPW) of 0.69 lm $W^{-1}$ at 8.2 V.) A discrete heterodinuclear molecular complex can serve as unprecedented multifunctional OLED materials for host-dopant assembly OLED based on a solution process. In an effort to search for a highly selective system that can operate at a very low concentration of cyanide, we combined three-coordinate borane as an energy donor and highly fluorescent BODIPY as an acceptor to construct a discrete and highly fluorescent borane-based sensor that exploits intramolecular excitation energy transfer transitions for the selective detection of cyanide. The coupling of borane as a donor and BODIPY as an acceptor leads to a boron-based receptor that shows a three-fold enhancement in fluorescence response for the selective sensing of cyanide ion by virtue of intramolecular energy-transfer transitions. In addition to high selectivity for cyanide over other relevant anions, highly sensitive ratiometric fluorescence response allows the detection of an extremely low level of cyanide. Studies on modifying the previous system to make it viable in an aqueous medium progressed. In an effort to search for a highly selective system that can capture cyanide in pure water, a novel cationic borane such as $B[2,6-Me_2-4-...