Analysis of thermally treated silica gel using Fourier transform ion cyclotron resonance mass spectrometry

It is possible to analyse thermally treated Stöberʹs silica compounds by laser microprobe mass spectrometry by studying two induced silica cluster families: SinO2n+1H− and SinO2n+1−. We show in this Letter that the ratio of the intensities of the peaks corresponding to SinO2n+1H−/SinO2n+1− decreases as the temperature of the thermal treatment increases. Moreover, we are able to support previous results obtained by 29Si NMR regarding the decrease of the concentration of hydroxyl groups in correlation with the increase of the temperature treatment of a silica sample.