By melting tetraphenylethene (TPE) and
1,2,4,5-tetraphenyl-1H-imidazole (TPI) units together
through different linking positions, three new fluorophores
are synthesized, and their optical, electronic and electro-
luminescence (EL) properties are fully studied. Owing to
the presence of TPE unit(s), these fluorophores are weak
emitters in solutions, but are induced to emit strongly in the
aggregated state, presenting typical aggregation-induced
emission characteristics. The experimental and computa-
tional results reveal that different connection patterns
between TPE and TPI could impact the molecular
conjugation greatly, leading to varied emission wave-
length, fluorescence quantum yield and EL performance in
organic light emitting diodes (OLEDs). The fluorophore
built by attaching TPE unit to the 1-position of imidazole
ring shows bluest fluorescence, and its EL device emits at
deep blue region (445 nm; CIE = (0.16, 0.15)). And the
device based on the fluorophore by linking TPE to the 2-
position of imidazole ring shows EL at 467 nm (CIE =
(0.17, 0.22)) with good efficiencies of 3.17 cd$A –1 , and
1.77%.

• Blue fluorophores comprised of tetraphenylethene and imidazole: aggregation-induced emission and electroluminescence