Study On The Electrochemical Behavior Of Metal Borides

Electrochemical batteries have been serving as convenient power sources for various portable electronic devices.The developing of portable electronic devices demands searching for new batery systems with higher energy density.It has been found that the boron element in metal borides is activated,and can be electrochemically oxidized with very high discharge capacity.We further studied the electrochemical behaviors of TiB2,Co-B UFAAP and Fe-B UFAAP,and the discharge products by XRD,XPS and ICP.We also discussed the possible mechanism of discharge reaction.Discharged at a constant rate of 100mA/g, TiB2 electrode gives out a discharge capacity of 800mAh/g in 30%KOH solution.In 20%KF solution,the discharge capacity of the second discharge stage can reach as high as 1400mAh/g.Co-B UFAAP and Fe-B UFAAP also exhibit electrochemical activities.When discharged at 100mA/g in 30%KOH solution, the discharge capacity of Fe-B UFAAP is 1200mAh/g,and Co-B UFAAP, 900mAh/g.Both Fe-B UFAAP and Co-B UFAAP anode show certain capability of recycling performance,but the discharge capacity decreased sharply with the increasing of cycling number.TiB2,Co-B UFAAP and Fe-B UFAAP also exhibit certain recyling performance as the anodes of Li-ion batteries in organic electrolyte.Our studies showed that metal borides have very high discharge capacity in water solutions and exhibit certain recycling capability in organic electrolyte.They may become very attractive anode materials.