脉冲激光沉积非晶态Ni-V2O5 复合薄膜及其电化学性能研究
A Study of Pulsed Laser Deposited Amorphous Nickel-V2O5 Composite Film and its Electrochemical Properties
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摘要: 首次报道了用355 nm脉冲激光沉积非晶态Ni-V2O5复合薄膜电极的电化学性能.采用不同摩尔比的NixV2O5 靶(x=0.1,0.3,0.5),在不同的基片温度(Ts)和O2气压力下制备了Ni-V2O5复合薄膜.XRD 和SEM测定表明, 在不锈钢基片上, Ts=300℃和氧气压力为14 Pa沉积0.5 h得到的是非晶态的Ni-V2O5薄膜.将此非晶态的Ni0.3V2O5薄膜电极用于锂电池的正极,与纯V2O5薄膜相比,不仅具有良好的放电速率性能和高的比容量,而且其充放电循环稳定性优异.该薄膜电极在放电Abstract: Amorphous Ni-V2O5 composite film cathodes with excellent electrochemical properties were successfully prepared by 355 nm pulsed laser reactive deposition for the first time. The optimum experimental conditions for the film deposition are:a laser fluency of 2 J/cm2,a temperature of substrate at 300℃,oxygen gas pressure 14 Pa,deposition duration 0 . 5 h and stainless steel used as a substrate material. X-ray diffraction (XRD)and scanning electron microscopy(SEM)analyses indicated that the Ni-V2O5 composite films deposited on stainless steel substrate are amorphous. Among the three composite films with different Ni-V2O5 molar ratio (x= 0.1,0.3,0.5),Ni0.3V2O5 (x= 0.3)composite film electrode exhibited best electrochemical performance. This film electrode retained a capacity of 200 mAh/g at a high rate of 20 C with excellent reversibility,upon cycling with no obvious fading over more than 1000 cycles. The improved specific capacity,rate capability and cycleability of amorphous Ni-V2O5 film electrodes demonstrate that these film electrodes could be used as a promising cathode material for all-solid-state thin film lithium ion rechargeable batteries.