Synthesis and characterization of [BaO-(10-x)ZrO₂-TiO₂-SiO₂-xCrO₃] type glass and glass ceramics

Abstract

Various glass compositions were prepared in a glassy system [25BaCO 3-(10-x) ZrO 2-20TiO 2-45SiO 2-xCrO 3 ] (x = 0, 2, 4, and 6) using melt-quenching technique. XRD patterns of glass and glass ceramics showed amorphous and crystalline nature. Density of glass and glass ceramics decreased from 3.4553 to 3.4381 g/cm 3 and 3.7485 to 3.1977 g/cm 3 with increasing concentration of CrO 3. DTA of the glasses revealed a shift in base line which suggests a change in specific heat and attributed to the glass transition temperature, T g. FTIR and Raman spectroscopic analysis indicated that an increasing doping of CrO 3 changes structural network by increasing number of nonbridging oxygens (NBO) within glassy matrix. These results revealed that bands toward low frequency side endorsed to the vibration of Ba 2+ metal cation, bending vibration of Si-O-Si and bonding formation of ZrO 2. Concentration of CrO 3, changed the microsture significantly and hence, a denser, fully developed mixed morphology was noticed with spherical grains of ZrO 2 , irregular shape of bazirite (BaZr 0.97 Ti 0.03 Si 3 O 9) phase and TiO 2 grains. Glass ceramic sample BZTS6C971 CrO 3 (x = 6) retains high value of dielectric constant, ~4555 due to space charge polarization. Hence, these glass ceramics might be useful for diverse applications such as in optical devices, electronic circuits, and multilayer ceramic capacitors.

Synthesis of a porous SiO2–H3BO3–V2O5–P2O5 glassy composite: structural and surface morphological behaviour for CO2 gas sensing applications

“…The XRD analysis shows diffused peaks with short-range order, confirming the amorphous nature of the prepared glass. 26 The absence of sharp peaks depicts that the prepared sample has no major phase formation or grain boundaries, which is further confirmed by the TEM characterization discussed later in this paper.…”

“…The polished sample was mounted on a copper stub with the help of a carbon tape, and SEM images were recorded at different magnifications with the help of SEM-Model: JSM-7610 F, Make: JEOL Ltd Japan. 26 The TEM images and diffraction patterns were recorded with the help of TEM (JEOL, Model: JEM 2100). A small quantity of finely powdered sample was taken and kept in an isopropyl alcohol bath for about 30 min.…”

“…Thus, the EDS spectrum reveals the desired elemental information about the synthesized porous glass sample. 26…”

“…The weight percentage of vanadium (V) is 32.56%, phosphorus (P) is 15.71%, silicon (Si) is 9.04%, and aluminium (Al) is 0.73%. The graph suggests that the weight percentage of oxygen (O) is 41.96% due to the contribution of oxides in the preparation of the glass sample 26…”

“…The prepared glass was taken out when the furnace was cooled to room temperature (30 °C). 7,26 The schematic diagram for glass preparation is shown in Fig. 1(a).…”