Laser-induced clustering dynamics of [(SiO 2) nX] − from porous silica powders

Abstract

The clustering dynamics of SiO 2-containing negative ion clusters generated from ultrafine amorphous SiO 2 powders with high specific surface area is investigated by XeCl excimer laser ablation time-of-flight mass spectrometry (TOF-MS). From the evolution of the mass spectra with the delay time and the number of laser irradiation shots, the key roles played by OH and OH − fragments from the surface silanol groups in the formation of SiO 2-containing negative ion clusters are discussed.