Oxidation process of white Si–O–C(–H) ceramics with various hydrogen contents

Investigation of photoluminescence of Si−O−C(−H) ceramics at an early stage of decarbonization by using high energy excitation

“…[10][11][12] Absolute carbon content in these ceramics was reduced to 70-75% of that obtained in an Ar atmosphere. At the same time, the hydrogen content was 2-4 times greater.…”

“…10,12,20 It suggests Figures 2(a) and 2(b) show PL spectra of S750, S800 and S850 under the HeCd laser and the ArF excimer laser excitations, respectively. Under the HeCd laser excitation, the stationary luminescence spectra of S750, S800 and S850 have the peaks at 400, 410 and 415 nm, respectively.…”

Boria Effects on the High Temperature Oxidation of Silicon Carbide

“…Volatilization of the organics in oxygenated and water vapor gas environments was found to reduce carbon retention in the heat treated glasses [78][79][80] . A preferable approach to reducing carbon retention in sol-gel coatings that would avoid SiC substrate oxidation during glass conversion is exposure of the coatings to hydrogen during glass conversion, which was found to decrease carbon concentration SiOC ceramics derived from silicone resin by the evolution of methane gas [81][82][83] . Determining the carbon bonding to the glass structure as part of the glass network or segregation in elemental forms 84 is an area of active investigation 85 , and it can have notable effects on the microstructure and high temperature properties of silica 86 and borosilicate sol-gel derived glasses 75 .…”

“…The synthesis also does not replicate binary SiO2-B2O3glasses, primarily due to carbon retention from partial organic volatilization during the gel-to-glass conversion 75 . The retained carbon is expected to oxidize in the high temperature oxygen environment 80,82,83 and might affect oxygen transport through the glass coating during exposure. Boria volatilization is also expected to occur during high temperature exposure 57 , thus changing the glass composition over the duration of the test.…”

In-situ monitoring of ion-beam luminescence of Si–O–C(–H) ceramics under proton-beam irradiation

“…13), 14) The effect of beam irradiation on the luminescence properties of SiOC(H) ceramics draws considerable interest. For amorphous and crystalline silica, beam irradiation often introduces various defects in the SiOSi network which greatly influence the optical properties of the irradiated silica.…”