Effective dielectric loss (tan δ) reduction of CaCu₃Ti₄O₁₂ (CCTO) via various addition of glasses

Abstract

Addition of various glasses has successfully reduced tan δ of CCTO-based ceramics. Less amounts (0-1.0 wt%) of glasses (BaO-SrO-Nb 2 O 5 -B 2 O 3 -SiO 2 [BSNBS] and SrO-B 2 O 3 -SiO 2 [SBS], respectively) were added into pure CCTO and sintered at 1040°C for 10 hours. The phase formation and microstructure of each sample were characterized using X-ray diffraction and scanning electron microscopy, respectively. The dielectric behavior of the samples was measured at 1 MHz. The addition of BSNBS and SBS glasses (≤0.5 wt%) successfully reduced tan δ of CCTO from 0.5 until 0.4 and 0.39, respectively, and simultaneously increased ε r .Smaller tan δ and ε r were further obtained when the added glasses were more than 0.5 wt%. These behaviors were due to segregation of glasses together with precipitation of CuO which decreased the grain size, and caused the presence of pores at grain boundaries. Therefore, small amount of various additions of glasses could modify the CCTO dielectric properties.

Wideband frequency tunability of CaCu3Ti4O12‐based dielectric resonator antennas via the addition of glass

“…Higher amounts of BSNBS glass contributed to the smaller grain size of CCTO. The glass addition seemed to have segregated CuO at the grain boundaries and restricted the CCTO’s grain growth as detected by EDX and XRD analyses reported in our previous work 30 . The presence of both glassy and CuO phases cannot be clearly seen on the surface of each sample but was detected by EDX analysis on the sample cross‐section.…”

“…The presence of both glassy and CuO phases cannot be clearly seen on the surface of each sample but was detected by EDX analysis on the sample cross‐section. The formation of CuO phase alongside major CCTO phase has also been proven by XRD analysis 30 . It is observed that the major peaks belong to CCTO in all composites since the maximum amount of each glass added was only 1 wt%.…”

“…The formation of CuO phase alongside major CCTO phase has also been proven by XRD analysis. 30 It is observed that the major peaks belong to CCTO in all composites since the maximum amount of each glass added was only 1 wt%. For each sample, only minor CuO phase was seen appearing at ~35.5° and ~38.6°.…”

“…The glass addition seemed to have segregated CuO at the grain boundaries and restricted the CCTO's grain growth as detected by EDX and XRD analyses reported in our previous work. 30 The presence of both glassy and CuO phases cannot be clearly seen on the surface of each sample but was detected by EDX analysis on the sample cross-section. The formation of CuO phase alongside major CCTO phase has also been proven by XRD analysis.…”

Tailorable Dielectric Performance of Niobium‐Modified Poly(hydridomethylsiloxane) Precursor‐Derived Ceramic Nanocomposites

“…One of the most interesting approaches used to decrease the tan δ is by incorporating glass ceramics, for instance, SiO 2 in a dielectric material. [ 29 ] High electrical resistance (≈15 MV cm −1 ) [ 30 ] coupled with low tan δ (3.8 × 10 −4 ) of SiO 2 reduces tan δ , thereby improving dielectric properties. However, such devices based on glass blending mandate specialized insulating materials to shield from electrical discharge, which increases the overall production cost.…”