Polymer-derived SiOC aerogel with hierarchical porosity through HF etching. Issue 10 (1st August 2016)

• Record Type: Journal Article
• Authors: Assefa, Dawit; Zera, Emanuele; Campostrini, Renzo; Soraru, Gian Domenico; Vakifahmetoglu, Cekdar
• Is Part Of: Ceramics international. Volume 42:Issue 10(2016)
• Page Start: 11805
• Page End: 11809
• Publication Date: 2016-08-01
• Subjects: Preceramic polymers -- SiOC -- High surface area -- Aerogels -- HF etching; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2016.04.101
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Silicon oxycarbide (SiOC) aerogels have been synthesized from preceramic polymers via pyrolysis in inert atmosphere at 1200 and 1300 °C. The as synthesized materials have a typical colloidal microstructure with mesoporosity in the range 10–50 nm and no microporosity. HF acid attack of the SiOC aerogels dissolves preferentially the SiO2 -rich phase and creates micro-and (small)mesopores (<10 nm) in the aerogels microstructure finally leading to a materials with hierarchical porosity. The HF post-pyrolysis treatment is more efficient for the SiOC aerogels pyrolyzed at the maximum temperature, i.e. 1300 °C, leading to a maximum value of specific surface area of 530 m 2 /g and total porosity of 0.649 cc/g.