en Research Paper Research Paper Silicon oxycarbide (SiOC) materials derived from silicone attracted great attention for their superior high-temperature behavior. In the present study, Si(Ti)OC and Si(Ti,Al)OC nanocomposites, in which alkoxide precursors were used with the main silicone precursor, have been compared with SiOC material. Although in SiOC, C was bonded with Si in a carbon-rich SiOC phase, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) showed that TiC was the preferred state for C atoms upon adding Ti into the system. This claim was also substantiated by Raman spectroscopy, where adding Ti into the system lowered the intensity of the D band, indicating the high affinity of C to form crystalline TiC. In the Si(Ti,Al)OC nanocomposites synthesized by adding AlCl₃ into the Si(Ti)OC system, mullite nanocrystals formed a superlattice structure with TiC. UV-vis spectra of the nanocomposites showed Si(Ti,Al)OC with mullite-TiC superlattice had a larger bandgap compared with Si(Ti)OC with only TiC nanocrystals. SiOC nanocomposite,mullite,TiC,polymer-derived ceramics 1 8 http://ijmse.iust.ac.ir/browse.php?a_code=A-10-1978-2&slc_lang=en&sid=1 Amirhosein Paryab amirparyab5@gmail.com 1800319475328460014724 1800319475328460014724 No Department of Materials Science and Engineering, Sharif University of technology, Tehran, Iran Toktam Godary t.godary@gmail.com 1800319475328460014725 1800319475328460014725 No Department of Materials Science and Engineering, Sharif University of technology, Tehran, Iran Sorosh Abdollahi soroshabdollahi@yahoo.com 1800319475328460014726 1800319475328460014726 No School of Metallurgy and Materials Engineering, Iran University of science and technology, Tehran, Iran Mohsen Anousheh mohsen.anousheh.ir@gmail.com 1800319475328460014727 1800319475328460014727 No Department of Materials Science and Engineering, Islamic Azad University Science and Research branch, Tehran, Iran Adrine Malek Khachatourian khachatourian@sharif.edu 1800319475328460014728 1800319475328460014728 Yes Department of Materials Science and Engineering, Sharif University of technology, Tehran, Iran