title: Unraveling the Mystery of Stöber Silica's Microporosity.
abstract: Puzzling aspects of the microporous structure of Stöber silica, including inconsistencies in the BET specific surface area and the long measurement time required for N2 adsorption, hinder further research on and potential applications of this material. In this work, Stöber silica samples prepared using systematic and detailed post-treatment methods were characterized by N2 adsorption, scanning electron microscopy, transmission electron microscopy, inductively coupled plasma optical emission spectrometry, elemental analysis, and Fourier transform infrared spectroscopy. We have found that the often overlooked sample preparation conditions may be the main causes that perplex the gas adsorption characterization results of Stöber silica samples. The pore-blocking processes associated with a variety of sample treatment methods are discussed in detail. Strong evidence for the particle growth model and pore-blocking mechanism involving ethoxyl groups, Si species, and condensation of silanols is provided. A remarkable result is that the measurement time is shortened from 1 month in our previous work to 2-3 days for samples with large specific surface areas. A suitable post-treatment condition is recommended to obtain microporous Stöber silica with a short measurement time, including water washing, low temperature drying without a vacuum, and a short storage time.
authors.affiliation: State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences , Guiyang, Guizhou 550081, China.|University of Chinese Academy of Sciences , Beijing 100049, China.|School of Chemistry and Materials Science, Guizhou Normal University , Guiyang, Guizhou 550001, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Li
authors.affiliation: State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences , Guiyang, Guizhou 550081, China.
authors.forename: Quan
authors.initials: Q
authors.lastname: Wan
authors.affiliation: State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences , Guiyang, Guizhou 550081, China.
authors.forename: Zonghua
authors.initials: Z
authors.lastname: Qin
authors.affiliation: State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences , Guiyang, Guizhou 550081, China.|University of Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Fu
authors.affiliation: State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences , Guiyang, Guizhou 550081, China.|University of Chinese Academy of Sciences , Beijing 100049, China.
authors.forename: Yuantao
authors.initials: Y
authors.lastname: Gu