The influence of the temperature on positron annihilation lifetime spectra in porous sol-gel glass doped with ag nanoparticles

Silver nanoparticles with continuous size distribution from 10 to 20 nm were incorporated into porous glass produced using sol-gel technique. Positron annihilation lifetime spectroscopy was used to compare obtained material with an undoped reference glass. The positron annihilation lifetime spectroscopy measurement were made in a broad temperature range (from -180°C to 200°C). The experimental lifetime values were compared with the predictions of the extended Tao-Eldrup model of the temperature range. Experimental results for the reference material were in agreement with the model, except for a small discrepancy at low temperatures. In doped material substantial changes and non-monotonous temperature dependences of intensity and lifetime values were observed. Heating the material to 200 °C resulted in reorganization of the material structure.