本文报道了TiB2作为阳极材料在中性水溶液中的电化学行为.结果表明TiB2在KF水溶液中释放出超高电化学容量:在电流密度为50 mA/g时,容量可以达到1300 mAh/g,超过目前报道的所有金属电极的容量.在放电过程中,二硼化钛中的硼发生电化学氧化反应生成硼氟酸根,而其中的钛则形成金属单质.因此二硼化钛可以作为一种阳极材料构建高比容量中性化学电源体系.
Titanium diborides were investigated as an anodic material for neutral aqueous batteries.It is revealed that this material shows superiorly high electrochemical activities in the neutral electrolytes.The discharge capacities observed for TiB2 reached 1300 mAh/g at the constant current density of 50 mA/g,exceeding all the metal electrodes reported so far.The electrooxidation of this compound was found to proceed via the electrochemical dissolution of boron to form borofluoride,while titanium remained unchanged at the electrode.These results suggest a possible use of the boride compounds as a new material for constructing neutral aqueous batteries with high electrochemical capacity and rate capability.
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