B_2O_3-SiO_2-ZnO-BaO-Al_2O_3 glass with different Al_2O_3 contents(1mol%, 3mol%, 5mol%, and 7mol%) was prepared, and it was intended to be used as lead-free and low-melting glass sealants for solid oxide fuel cells....B_2O_3-SiO_2-ZnO-BaO-Al_2O_3 glass with different Al_2O_3 contents(1mol%, 3mol%, 5mol%, and 7mol%) was prepared, and it was intended to be used as lead-free and low-melting glass sealants for solid oxide fuel cells. The effects of Al_2O_3 content on the structures, thermal properties, and sintering behaviors of the B_2O_3-SiO_2-ZnO-BaO-Al_2O_3 glass were investigated in detail. The Al_2O_3 content largely influenced the structures and thermal properties of the glass. When the Al_2O_3 content 5mol%, the transition temperature of the glass decreased with the Al_2O_3 content, while the crystallization temperature increased with the Al_2O_3 content. However, higher Al_2O_3 content degraded the stability of the glass. The B_2O_3-SiO_2-ZnO-BaO-Al_2O_3 glass with 5 mol% Al_2O_3 content exhibits the optimal sintering densification characteristics and can be used as glass sealants for solid oxide fuel cells.展开更多
The 40Bi2O3-30B2O3-(30-x)ZnO-xSrO (x=0-15mol%,BBZSr) glass system was prepared by the conventional melt quenching method.The effect of SrO addition on structure,thermal properties,chemical stability and sealing perfor...The 40Bi2O3-30B2O3-(30-x)ZnO-xSrO (x=0-15mol%,BBZSr) glass system was prepared by the conventional melt quenching method.The effect of SrO addition on structure,thermal properties,chemical stability and sealing performance of BBZSr glass were investigated thoroughly.The experimental results show that the total proportions of [BO3] group and [BO4] group decrease and the vibrations of [BiO3] group and [BiO6] group become weaker with the increase of SrO addition content,suggesting the glass network structure is strengthened owing to the SrO addition.Hence,both the thermal and chemical stability were significantly improved as the SrO content was increased.When the SrO content increased from 0 to 15mol%,the glass transition temperature and softening temperature slightly increased from 380 to 388 ℃ and from 392.7 to 402.2 ℃,respectively,meanwhile the coefficient of thermal expansion also increased from 10.49×10^-6 to 11.16×10^-6/℃ (30-300 ℃).The BBZSr glass with 15mol% SrO exhibited excellent comprehensive properties with low glass transition temperature(384.9 ℃),low softening temperature(400.3 ℃),high coefficient of thermal expansion (11.14×10^-6 ℃,30-300 ℃),good thermal and chemical stability.Besides,the glass had the good wetting behavior and sealing performance for Al-50%Si alloy.展开更多
Among new low-melting-point glasses, bismuth ate glass is deemed to have the most potential as an environmentally friendly replacement for polluting Pb-containing glasses. Current studies of boro-bismuthate glasses fo...Among new low-melting-point glasses, bismuth ate glass is deemed to have the most potential as an environmentally friendly replacement for polluting Pb-containing glasses. Current studies of boro-bismuthate glasses focus on the structural influence of the additional oxide in the context of low-melting-point electronic sealing applications. In this study, the structure of quaternary Bi2O3- ZnO-B2O3-BaO glasses was investigated spectroscopic ally, with Fourier-transform-infrared (FT-IR) and Raman spectra recorded for glasses with different main oxide contents. Signals in the FT-IR are mainly observed around 500 cm﹣1, 720 cm﹣1, 840 cm﹣1, 980 - 1080 cm﹣1, and 1200 - 1500 cm﹣1, while the Raman scattering peaks are located at 130 cm﹣1, 390 cm﹣1, 575 cm﹣1, 920 cm﹣1, and 1250 cm﹣1. The glasses are mainly structured around [BO3] units and the numbers of [BiO6] and [BiO3] units increase with the Bi2O3 content increasing. Concurrently, the FT-IR absorption peaks associated with [BO4] units shift to lower wave numbers, indicating a loosening of the glass structure. However, as the B2O3 content is increased, the numbers of [BO3] and [BO4] units increase, while those of [BiO3] and [BiO6] units decrease, highlighting a densification of the glass structure. ZnO acts as a network modifier in these glasses.展开更多
基金Funded by the Jiangxi Provincial Department of Education(KJLD13008)the National Natural Science Foundation of China(number 51362020)the Research Fund for the Doctoral Program of Higher Education(20123601110006)
文摘B_2O_3-SiO_2-ZnO-BaO-Al_2O_3 glass with different Al_2O_3 contents(1mol%, 3mol%, 5mol%, and 7mol%) was prepared, and it was intended to be used as lead-free and low-melting glass sealants for solid oxide fuel cells. The effects of Al_2O_3 content on the structures, thermal properties, and sintering behaviors of the B_2O_3-SiO_2-ZnO-BaO-Al_2O_3 glass were investigated in detail. The Al_2O_3 content largely influenced the structures and thermal properties of the glass. When the Al_2O_3 content 5mol%, the transition temperature of the glass decreased with the Al_2O_3 content, while the crystallization temperature increased with the Al_2O_3 content. However, higher Al_2O_3 content degraded the stability of the glass. The B_2O_3-SiO_2-ZnO-BaO-Al_2O_3 glass with 5 mol% Al_2O_3 content exhibits the optimal sintering densification characteristics and can be used as glass sealants for solid oxide fuel cells.
基金the Open Project Program of Key Laboratory of Inorganic Functional Materials and Devices,Chinese Academy of Sciences(No.KLIFMD-2018-06)。
文摘The 40Bi2O3-30B2O3-(30-x)ZnO-xSrO (x=0-15mol%,BBZSr) glass system was prepared by the conventional melt quenching method.The effect of SrO addition on structure,thermal properties,chemical stability and sealing performance of BBZSr glass were investigated thoroughly.The experimental results show that the total proportions of [BO3] group and [BO4] group decrease and the vibrations of [BiO3] group and [BiO6] group become weaker with the increase of SrO addition content,suggesting the glass network structure is strengthened owing to the SrO addition.Hence,both the thermal and chemical stability were significantly improved as the SrO content was increased.When the SrO content increased from 0 to 15mol%,the glass transition temperature and softening temperature slightly increased from 380 to 388 ℃ and from 392.7 to 402.2 ℃,respectively,meanwhile the coefficient of thermal expansion also increased from 10.49×10^-6 to 11.16×10^-6/℃ (30-300 ℃).The BBZSr glass with 15mol% SrO exhibited excellent comprehensive properties with low glass transition temperature(384.9 ℃),low softening temperature(400.3 ℃),high coefficient of thermal expansion (11.14×10^-6 ℃,30-300 ℃),good thermal and chemical stability.Besides,the glass had the good wetting behavior and sealing performance for Al-50%Si alloy.
文摘Among new low-melting-point glasses, bismuth ate glass is deemed to have the most potential as an environmentally friendly replacement for polluting Pb-containing glasses. Current studies of boro-bismuthate glasses focus on the structural influence of the additional oxide in the context of low-melting-point electronic sealing applications. In this study, the structure of quaternary Bi2O3- ZnO-B2O3-BaO glasses was investigated spectroscopic ally, with Fourier-transform-infrared (FT-IR) and Raman spectra recorded for glasses with different main oxide contents. Signals in the FT-IR are mainly observed around 500 cm﹣1, 720 cm﹣1, 840 cm﹣1, 980 - 1080 cm﹣1, and 1200 - 1500 cm﹣1, while the Raman scattering peaks are located at 130 cm﹣1, 390 cm﹣1, 575 cm﹣1, 920 cm﹣1, and 1250 cm﹣1. The glasses are mainly structured around [BO3] units and the numbers of [BiO6] and [BiO3] units increase with the Bi2O3 content increasing. Concurrently, the FT-IR absorption peaks associated with [BO4] units shift to lower wave numbers, indicating a loosening of the glass structure. However, as the B2O3 content is increased, the numbers of [BO3] and [BO4] units increase, while those of [BiO3] and [BiO6] units decrease, highlighting a densification of the glass structure. ZnO acts as a network modifier in these glasses.