TY - JOUR
T1 - Positronium annihilation and pore surface chemistry in mesoporous silica films
AU - He, Chunqing
AU - Oka, Toshitaka
AU - Kobayashi, Yoshinori
AU - Oshima, Nagayasu
AU - Ohdaira, Toshiyuki
AU - Kinomura, Atsushi
AU - Suzuki, Ryoichi
N1 - Funding Information:
Financial support to our porous film studies from the New Energy and Industrial Technology Development Organization (NEDO) is formally appreciated. One of the authors (C.H.) is grateful to the Japan Society for the Promotion of Science (JSPS) for the financial support. The authors are indebted to the referee for valuable comments and suggestions. K. Ito is appreciated for his helpful comments and assistance in gas adsorption experiments.
PY - 2007
Y1 - 2007
N2 - Lifetimes of ortho-positronium in mesoporous silica films were measured before and after surface trimethylsilylation of -OH groups. Variations of positronium lifetimes in the mesopores upon the surface modification indicate that the interaction between positronium and the pore surface is weakened in the pores, whose surface is covered with -C H3 groups, in comparison with those covered with -OH groups. This is consistent with the authors' previous observation that positronium slowing down is less efficient in the pores covered with -C H3 groups. The present work demonstrates that in the porosimetric application of positron annihilation lifetime spectroscopy, the interaction between positronium and the pore surface has to be properly taken into consideration.
AB - Lifetimes of ortho-positronium in mesoporous silica films were measured before and after surface trimethylsilylation of -OH groups. Variations of positronium lifetimes in the mesopores upon the surface modification indicate that the interaction between positronium and the pore surface is weakened in the pores, whose surface is covered with -C H3 groups, in comparison with those covered with -OH groups. This is consistent with the authors' previous observation that positronium slowing down is less efficient in the pores covered with -C H3 groups. The present work demonstrates that in the porosimetric application of positron annihilation lifetime spectroscopy, the interaction between positronium and the pore surface has to be properly taken into consideration.
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U2 - 10.1063/1.2756310
DO - 10.1063/1.2756310
M3 - Article
AN - SCOPUS:34547189128
SN - 0003-6951
VL - 91
JO - Applied Physics Letters
JF - Applied Physics Letters
IS - 2
M1 - 024102
ER -