Synthesis of non-oxide materials applicable in corrosive media

Iranian researchers from Najafabad and Shahreza Branches of Islamic Azad Universities obtained SiO2-Al2O3-C mixture at nanometric scale to synthesize non-oxide materials by precisely changing the ratio of Si to Al. Results of the research have applications in modifying sintering process by using SiAlON synthesized in ceramic frames, and also in the synthesis of beds for catalysts that operate at high temperature or at highly corrosive environment. Accurate change in the ratio of Si to Al in SiO2-Al2O3-C nanocomposite is among the unique characteristics of Al-SBA-15 nanocomposite to synthesize SiAlON through carbothermal reduction and nitridation process. The aim of the research was to produce non-oxide nanostructure that has application as an additive to modify sintering process. In the present study, SBA-15 and Al-SBA-15 were respectively synthesized to make sure Al existed in the structure of SBA-15 mesopore. Next and in order to synthesize SiAlON through carbothermal and nitridation method, various ratios of carbon functions obtained from poly(4-vinylpyridine) and polyacrylamide in addition to C/Al-SBA-15 were used to synthesize Al-SBA-15 nanocomposite. The samples were next cooked at nitrogen atmosphere at 1450°C with heat rate of 10°C/min and resistance time of 3 hours at maximum temperature to synthesize SiAlON. In common SiAlON synthesis methods, the value of Z parameter usually varies in the composition of the sample since the ratio of Si to Al is not controlled precisely. This problem has been almost solved by using silicate mesopore nanocomposites doped with Al. Results of the research have been published in details in Ceramics International, vol. 39, issue 6, August 2013, pp. 6293-6298. It has been classified among the top articles in the field of nanotechnology.