• YINGJIE QIAO

Articles written in Bulletin of Materials Science

• Effects of calcination temperatures on the morphology, architecture and dielectric properties of BCZT ceramics

(Ba$_{0.85}$Ca$_{0.15}$)(Zr$_{0.1}$Ti$_{0.9}$)O$_3$ (BCZT) ceramics were prepared by a simple sol–gel method. The effects of calcining temperature on the formation of BCZT ceramics were investigated in detail. The morphological changes and phase transformation of BCZT ceramics were analysed by X-ray diffraction and scanning electron microscopy. It is found that the calcined temperature determines the formation of a crystal phase, crystallinity and grain size. For dielectric properties, dielectric constant was increased first, and then decreased with increasing calcination temperature, in which the maximumdielectric constant of 2732 was achieved at 650$^{\circ}$C under a low-frequency alternating electric field. This may be attributed to the high crystallinity, density and fewer surface defects of BCZT ceramics. The optimum calcination temperature helps to understand the dielectric properties, which indicates that BCZT ceramics are promising lead-free candidates for widely used lead-based piezoelectric materials.

• Photodegradation of methylene blue over a new down-shifting luminescence catalyst

TiO$_2$ nanotube arrays prepared by anodization technology are modified with a samarium ion (Sm$^{3+}$) by a hydrothermal method for use in photodegradation of methylene blue (MB). The samarium ion as a down-shifting luminescence material can improve UV radiation harvesting to increase visible light utilization. The efficiency of the photocatalytic activity for the modified-TiO$_2$ nanotube arrays in degradation of MB was investigated under UV–Vis light irradiation. The results show that Sm–TiO$_2$ nanotubes can increase the photocatalytic efficiency of MB. When TiO$_2$ nanotubes are modified by 0.02 M Sm$^{3+}$, MB can be almost completely degraded when compared with bare TiO$_2$ nanotubes. This indicates that TiO$_2$ nanotubes structure, surface area and good UV radiation harvesting play important roles in the degradation of MB.

• # Bulletin of Materials Science

Volume 43, 2020
All articles
Continuous Article Publishing mode

• # Dr Shanti Swarup Bhatnagar for Science and Technology

Posted on October 12, 2020

Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020