Reaction Synthesis and Discharge Performance of Binary Vanadium Borides

doi:10.15541/jim20160389

Abstract

Abstract:

Vanadium boride compound powders with different compositions were prepared by reactive synthesis at 1500℃ from elemental powders. Then, with the obtained powders as active materials, Ni powder as conductive agent and NH₄HCO₃ as space-holder, the porous anodes of V-xB/Ni (x=2/3~2) were fabricated by powder metallurgy (PM), respectively. The effects of V-xB compounds with different phases on the discharge performance of the assembled air batteries were studied. The results show that the single-phased VB₂ powder can be obtained from the raw powder with the atomic ratio of V:B=1:2, and so does the VB powder. As for atomic ratio of V:B=3:2, the synthesized powder consists of V₃B₂ and a small amount of VB, while the ratio of V:B=2:3 yields the phase composition of V₂B₃, V₃B₄ and minor VB₂. The prepared V-xB/Ni anodes with porosity of 60.25%-61.75% exhibit good discharge performance, and their capacity can reach the range of 6129-7901 mAh while specific capacity is 2724-3511 mAh/g. With the increase of B content, the discharge performance of V-xB/Ni anodes shows a significant improvement. In comparison, the porous V-2B/Ni anode possesses the superior discharge properties with discharge capacity of 3512 mAh/g, coulombic efficiency of 86.5% and specific energy of 2504 Wh/kg.

Key words: reactive synthesis, V-xB compounds, powder metallurgy, air battery

CLC Number:

TQ174

PAN Yu, LU Xin, WEI Zhi-Guo, WANG Guo-Qing, QU Xuan-Hui. Reaction Synthesis and Discharge Performance of Binary Vanadium Borides[J]. Journal of Inorganic Materials, 2017, 32(4): 407-412.

Figures/Tables 8

Fig. 1 XRD patterns of V-xB compounds powder by high- temperature synthesis

Fig. 2 XRD patterns of V-xB/Ni anodes by low-temperature sintering

Fig. 3 Porosity and density of different V-xB/Ni anodes

Fig. 4 SEM images of porous V-xB/Ni anodes(a) V-(2/3)B/Ni; (b) V-B/Ni; (c) V-(3/2)B/Ni; (d) V-2B/Ni

Fig. 5 Cyclic voltammograms of V-xB/Ni anodes in 6 mol/L KOH solution

Fig. 6 Discharge curves of V-xB/Ni anodes in 6 mol/L KOH solution at constant current of 100 mA

Table 1 Discharge property parameters of air cell assembled by V-xB/Ni anodes

Anodes	Voltage /V	Theoretical capacity/ (mAh·g^-1)	Capacity /mAh	Specific capacity/ (mAh·g^-1)	Percentage of theoretical capacity/%	Specific energy/ (Wh·kg^-1)
V-(2/3)B/Ni	0.67	3410	6129	2724	79.9%	1790
V-B/Ni	0.63	3573	6291	2796	78.3%	1723
V-(3/2)B/Ni	0.69	3735	6776	3012	80.6%	2059
V-2B/Ni	0.72	4060	7901	3512	86.5%	2504

Fig. 7 XRD patterns of V-xB/Ni anodes after discharge

References 18

[1]	LIU Q, WANG Y B, DAI L, et al.Scalable fabrication of nanoporous carbon fiber films as bifunctional catalytic electrodes for flexible Zn-air batteries. Adv. Mater., 2016, 28: 3000-3006.
[2]	ZHU M J, YUAN Z S, SANG L, et al.Research progresses of metal/air batteries. Journal of Power Sources, 2012, 36(12): 1953-1955.
[3]	NG S H, WANG J Z, WEXLER D, et al.Highly reversible lithium storage in spheroidal carbon-coated silicon nanocomposites as anodes for lithium-ion batteries. Angew. Chem. Int. Ed., 2006, 45(41): 6896-6899.
[4]	HE S Y, ZENG J B, JIANG F M.Numerical reconstruction and characterization analysis of microstructure of lithium-ion battery graphite anode. Journal of Inorganic Materials, 2015, 30(9): 906-912.
[5]	LEFLER M, STUART J, PARKEY J, et al.Higher capacity, improved conductive matrix VB2/air batteries. Journal of The Electrochemical Society, 2016, 163(5): A781-A784.
[6]	LI Y, DAI H.Recent advances in zinc-air batteries. Chem. Soc. Rev., 2014, 43: 5257-5275.
[7]	Stuart J, HOHENADEL A, LI X G, et al.The net discharge mechanism of the VB2/air battery. Journal of The Electrochemical Society, 2015, 162(1): A192-A197.
[8]	LICHT S, HETTIGE C, LAU J, et al.Nano-VB2 synthesis from elemental vanadium and boron: nano-VB2 anode∕air batteries. Electrochemical and Solid-State Letters, 2012, 15(1): A12-A14.
[9]	WANG Y D, GUANG X Y, PAN M.Mechanochemical synthesis and high-capacity performances of transition-metal borides as aqueous anode materials. Chin. Sci. Bull., 2012, 57(32): 4225-4228.
[10]	RHODES C, STUART J, LOPEZ R, et al.Evaluation of properties and performance of nanoscopic materials in vanadium diboride/air batteries. Journal of Power Sources, 2013, 239: 244-252.
[11]	STEVEN A, PER O, MICHAEL T K, et al.A novel high power density borohydride-air cell. Journal of Power Sources, 1999, 84(1): 130-133.
[12]	WANG Y D, AI X P, YANG H X.A study of metal borides as high capacity anode materials for aqueous primary batteries. Electrochemistry, 2005, 11(1): 16-19.
[13]	WANG Y D, GUANG X Y, CAO Y L, et al.Mechanochemical synthesis and electrochemical characterization of VBx as high capacity anode materialsfor batteries. Journal of Alloys and Compounds, 2010, 501: L12-L14.
[14]	LICHT S, WU H, YU X, et al.Renewable highest capacity VB2/air energy storage. Chem. Commun. (Camb), 2008, 28(28): 3257-3259.
[15]	YEH C L, WANG H J.Combustion synthesis of vanadium borides. Journal of Alloys and Compounds, 2011, 509: 3257-3261.
[16]	STUART L, GHOSH S, WANG B H, et al.Nanoparticle facilitated charge transfer and voltage of a high capacity VB2 anode. Electrochemical and Solid-State Letters, 2011, 14(6): A83-A85.
[17]	STUART J, LOPEZ R, LAU J, et al.Fabrication of VB2/air cells for electrochemical testing. Journal of Visualized Experiments, 2013, 78: 1-7.
[18]	WEI ZHI-GUO, LU XIN, TONG JIAN-BO, et al.Preparation and discharge performance of porous VB2 anodes for high capacity VB2-air battery. Journal of Inorganic Materials, 2017, 32(2): 122-126.