Fluorescence line narrowing and lifetime measurements are used to char
acterize the extents of clustering and hydroxyl quenching, respectivel
y, in Eu3+-doped sol-gel silica glasses prepared using europium triflu
oromethanesulfonate (triflate). A triflate ((CF3SO3)(3)Eu) rather than
a traditional nitrate (Eu(NO3)(3) . 6H(2)O) precursor is used as the
rare earth ion dopant in order to determine the feasibility of effecti
ng chemical dehydroxylation via in situ fluorination by incorporating
fluorine directly as a ligand substituent of the Eu3+ precursor. In sa
mples doped only with Eu3+, the use of the triflate precursor leads to
no noticeable differences in hydroxyl quenching of Eu3+ fluorescence
or Eu3+ aggregation relative to samples prepared with a nitrate precur
sor. Beneficial effects are observed, however, in samples codoped with
Al3+ or Sr2+. When Al3+ or Sr2+ is included in the synthesis, a reduc
tion in hydroxyl quenching of Eu3+ is observed when the triflate precu
rsor is used relative to the nitrate precursor. In addition, (CF3SO3)(
3)Al is found to be as effective at inhibiting Eu3+ clustering as the
previously reported Al(NO3)(3) . 9H(2)O and (C4H9O)(2)Al-O-Si(OC2H5)3
precursors. The effect of incoporating fluorine via FSi(OC2H5)(3) is a
lso briefly considered and gives mixed results which differ for nitrat
e and triflate Eu3+ precursors.