Study of mesoporous silica films by positron annihilation based on a slow positron beam: Effects of preparation conditions on pore size and open porosity

被引：17

作者：

He, Chunqing ^{[1
]}

Suzuki, Ryoichi ^{[1
]}

Ohdaira, Toshiyuki ^{[1
]}

Oshima, Nagayasu ^{[1
]}

Kinomura, Atsushi ^{[1
]}

Muramatsu, Makoto ^{[1
]}

Kobayashi, Yoshinori ^{[1
]}

机构：

[1] Natl Inst Adv Ind Sci & Technol, AIST, Tsukuba, Ibaraki 3058565, Japan

来源：

CHEMICAL PHYSICS | 2007年 / 331卷 / 2-3期

基金：

日本学术振兴会;

关键词：

positronium; slow positron beam; micropore; mesopore; copolymer; silica film;

D O I：

10.1016/j.chemphys.2006.10.016

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Positron annihilation spectroscopy (PAS) based on an intense pulsed slow positron beam was applied to the study of mesoporous silica films, synthesized using tetraethyl orthosilicate (TEOS) as the network precursor and a triblock copolymer (EO106PO70EO106) as the structure-directing agent. With positron annihilation lifetime spectroscopy (PALS), pore sizes were obtained from ortho-positronium (o-Ps) lifetimes of the films capped with a 20 nm thick SiO2 layer. Influences of preparation conditions such as heating, TEOS vapor infiltration and precursor solution ageing on the pore size were studied. Moreover, the effect of ageing of the precursor solution on film pore interconnectivity/open porosity was investigated through lifetime-energy correlation measurements by observing intrinsic annihilation of o-Ps diffused out from the uncapped film surface. (c) 2006 Elsevier B.V. All rights reserved.

引用

页码：213 / 218

页数：6