You are not logged in Total: 7journals, 20,687articles Online
AccountAccount
Login / Register
Forgot Login?
 
Main menuMain menu
What's new
Journal list
Visiting ranking
Phrase ranking
Polls
About us
 
SearchSearch
 
Journal Site
Advanced Search
 

Home  >  Journal list  >  Journal of the Ceramic Society of Japan  >  Vol.123  No.1441 (September) (2015)  >  pp.732-738

Journal of the Ceramic Society of Japan
<<Previous article Vol.123  No.1441 (September) (2015)   pp.732 - 738 Next article>>

Polymer-derived amorphous silica-based inorganic–organic hybrids having alkoxy groups: intermediates for synthesizing microporous amorphous silica materials

Mohd Nazri MOHD SOKRI1) 2), Takahiro ONISHI1), Zineb MOULINE1), Yusuke DAIKO1) 3), Sawao HONDA1) 3), Yuji IWAMOTO1) 3)
1) Department of Frontier Materials, Graduate School of Engineering, Nagoya Institute of Technology 2) Department of Renewable Energy and Advanced Membrane Technology Research Centre, Faculty of Petroleum and Renewable Energy Engineering, Universiti Teknologi Malaysia (UTM) 3) CREST, Japan Science and Technology Agency

Alkoxy group-functionalized amorphous silica-based inorganic–organic hybrid materials were designed through polymer precursor route, in order to develop a novel route for the fabrication of microporous amorphous silica-based materials. Commercial perhydropolysilazane (PHPS) was chemically modified with alcohols (R-OH, R = n-C5H11OH, n-C10H21OH) at a PHPS (Si basis) to ROH molar ratio of 4/1, and subsequently oxidized to afford alkoxy group-functionalized amorphous silica by exposure to aqueous ammonia vapours at room temperature. Then, the oxidized materials were heat-treated at 600°C in air. Nitrogen sorption analysis revealed that micropore volume of the amorphous silica increased upon alkoxy group-functionalization prior to the heat treatment. As a result, higher micropore volume of 0.204 cm3/g was achieved, with a specific surface area of 387 m2/g for the PHPS-derived amorphous silica chemically modified with n-C10H21OH at the Si/n-C10H21OH molar ratio of 2/1. The micropores evaluated by the SF method were in the size range of 0.43 to 1.6 nm, and the resulting micropore size distribution plot exhibited a peak at 0.43 nm. The in-situ formation of the microporosity was further studied by the simultaneous thermogravimetry-mass spectrometry analysis. The relationship between the number of carbon atoms in the alkoxy group, the evolution of gaseous species during the heat treatment and the resulting microporosity is discussed.


Keyword:
Perhydropolysilazane, Inorganic–organic silica-based hybrids, Amorphous silica, Microporosity, Thermogravimetry-mass spectrometry, Polymer-derived ceramics

Received: April 16, 2015
Accepted: June 01, 2015 , Published online: September 01, 2015

PDFPDF file (J-STAGE)J-STAGEJ-STAGE


SPARC Japan

Terms of Use | Privacy Policy