Evaluation of adsorptive properties of nano pores

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K17788
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Petrology/Mineralogy/Economic geology
• Research Institution: National Institute for Materials Science
• Principal Investigator: Nishiyama Naoki 国立研究開発法人物質・材料研究機構, 機能性材料研究拠点, 外来研究者 (30746334)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 吸着 / 電気二重層 / 表面電荷密度 / ナノ間隙 / 鉱物/水界面

Outline of Final Research Achievements

To study the effect of pore size on ion adsorptive properties, we conducted acid/base titration experiments using nanoporous silica powders of different pore sizes. Ionic strengths in the titration experiments were adjusted to be 1 and 100 mM using NaCl. The nanoporous silica powders having average pore diameters of 1.2 nm and 50 nm were used. It was found that the silica surfaces of nanopores were less negatively charged with decreasing the pore size. Because the formation of >Si-O－ and >Si-O－Na+ sites results in the negative charges, the finding suggests that as the pore size decreases the sum of >Si-O－ and >Si-O－Na+ sites decreases and alternatively >Si-OH site increases.

Free Research Field

岩石-水反応