Ga. Hebbink et al., Increased luminescent lifetimes of Ln(3+) complexes emitting in the near-infrared as a result of deuteration, EUR J ORG C, (21), 2001, pp. 4101-4106
The luminescence of lanthanide(III) ions emitting in the near-infrared regi
on is ideally suited for telecommunications applications, and a number of a
pplications have been developed. These are in general based on inorganic ma
trices, but polymer-based matrices would have advantages in device fabricat
ion. In organic matrices, however, molecular vibrations in the matrix quenc
h the excited state of luminescent lanthanide ions. Replacement of strongly
quenching groups such as C-H oscillators by more weakly quenching groups e
nhances the luminescence lifetime and hence also the luminescence quantum y
ield. This article reports a synthesis route developed in order to deuterat
e all C-H groups that contribute to the quenching in an organic lanthanide
complex. The luminescences of three near-infrared emitting lanthanide ions
- Nd3+, Er3+, and Yb3+ - were measured. The maximum effect achieved upon de
uteration is a factor of 2-3, but lifetimes remain in the microsecond regio
n (1-Nd3+: 5.5 mus; 1-Yb3+: 52.3 mus; 1(.)Er(3+): 5.4 mus).