Articles written in Bulletin of Materials Science

    • Microstructure and microwave dielectric properties of (Zn1–𝑥Mg𝑥)2SiO4 ceramics

      Bo Li Ying Yuan Shuren Zhang Hongmei Jiang

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      (ZnMg)2SiO4 powders was prepared by the sol–gel process, and the microstructure and dielectric properties of (Zn1–𝑥Mg𝑥)2SiO4 microwave materials were investigated systematically. TG-DSC and XRD analyzes for gels indicate that the (ZnMg)2SiO4 with pure willemite phase could be obtained at low temperature of 850°C. Further, XRD illustrates that just small amounts of Mg can be incorporated into Zn2SiO4 lattice, and the solid solution limit of Mg in Zn2SiO4 is about 𝑥 = 0.1. By appropriate Mg substitution for Zn, the sintering range is widened and the sintering temperature of Zn2SiO4 ceramics can be lowered effectively. SEM shows that Mg-substitution for Zn can promote the grain growth of Zn2SiO4. Moreover, the microwave dielectric properties strongly depended on the substitution content of Mg and sintering temperatures. (Zn0.8Mg0.2)2SiO4 dielectrics sintered at 1170°C show the condense microstructure with small uniform grains and best microwave properties: 𝜀r = 6.3, 𝑄 × 𝑓 = 189800 GHz and 𝜏f = –63 ppm/°C.

    • Insights into the charge storage mechanism of Na$_3$V$_2$(PO$_4$)$_3$ cathode in sodium-ion batteries


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      The NASICON-type Na$_3$V$_2$(PO$_4$)$_3$ (NVP) material was synthesized through the sol–gel route and characterized as cathode in sodium-ion battery by the cyclic voltammetry (CV), galvanostatic intermittent titration technique (GITT) as well as electrochemical impedance spectroscopy (EIS) methods. Scan rate-dependent CV demonstrates an approximate diffusion-type behaviour and gives the diffusion coefficient value 5.24 ${\times}$ 10$^{–11}$ cm$^2$ s$^{–1}$ for Na$^+$ in NVP. Both GITT and EIS tests demonstrate the U-shape diffusion coefficients for Na$^+$ correlated to stoichiometry ranging from 10$^{–16}$ to 10$^{–11}$ cm$^2$ s$^{–1}$, where bottom of the diffusion rate corresponding the plateau voltage well matches with CV data. The strong interaction between the main skeleton and Na$^+$ during the two-phase reaction as demonstrated by the X-ray diffraction results was believed as the reason that reduces the diffusion rate of Na$^+$ at the plateau voltage.

  • Bulletin of Materials Science | News

    • 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

      Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
      Physical Sciences 2020

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

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