Temperature-Dependent Fluorescence in Au₁₀Nanoclusters

We report here the temperature dependence studies of the fluorescence of histidine-protected Au 10 nanoclusters. We conclude from the experiments that the process involves thermally activated nonradiative trapping with an activation energy of 103 meV. At increased temperatures, the peak energy of fluorescence was found to exhibit a small blue shift, largely due to lattice torsional fluctuation, whereas the electron–phonon scattering plays a minor role. Moreover, the bandwidth of fluorescence also increased slightly as a result of enhanced surface/defect/impurity scattering. We suggest that electron–electron interactions and surface/defect/impurity scattering play dominant roles in such a Au 10 nanocluster.