SnO-GeO2-Sb2O3 glass anode network mixed with different Ba2+ fractions: Investigations on Na-ion storage capacity and stability

• Published in: Journal of non-crystalline solids Vol. 506; pp. 80 - 87
• Main Authors: Gandi, Suman, Chinta, Srinivasa Rao, Ghoshal, Partha, Ravuri, Balaji Rao
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.02.2019
• Subjects: CV studies; EIS studies; High-energy ball-milling; Na-ion batteries; SnO-GeO2-Sb2O3 glass anode network; CV studies; SnO-GeO2-Sb2O3 glass anode network; High-energy ball-milling; EIS studies; Na-ion batteries
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/j.jnoncrysol.2018.11.028

Microstructure and electrochemical characteristics of glass anode composition (100-x) (0.7[0.625SnO-0.375GeO2]-0.3Sb2O3)-xBaO (x = 0, 2, 4, 6 and 8 mol%, labeled as Bx) for the sodium battery is analyzed. The absence of peaks in the XRD traces related to glass former (Sb2O3) after discharging is directly confirmed that the antimony content retains its amorphous phase even after the samples are being discharged. Several nanosized amorphous intermediate domains are precipitated in the bright region of Sn-Ge-Sb glass network as appeared in TEM results. Except for the sample B6, all the other samples exhibited two sloping sodiation and de-sodiation plateaus which are almost constant at around 0.62 V and 0.14 V due to the formation of amorphous intermediates domains such as Na9Sn4 and NaSn3 in the glass network. The initial discharge capacity achieved to be highest for B6 sample (838 mA h g−1) and loss of discharge capacity is up to ~31.18% even at high rate 5C. A systematic study can monitor the stable cycle performance and shed light on the design of target glass anode with high capacity and stability. •Sb2O3 content in glass samples retains its amorphous phase even after sodiation.•Amorphous intermediate domains facilitate wider active centers for Na+ ion.•Agglomeration of Sn particles controls by amorphous intermediate phase Na9Sn4•Initial discharge capacity achieved to be highest for B6 sample (838 mA h g−1).•Loss in discharge capacity is up to ~31.18% even at high rate 5C.