超声波沉淀法制备Y掺杂纳米多相Ni(OH)2及其性能研究

Study on the Preparation of Y-doped Multiphase Nano-Ni(OH)2 by a Supersonic Precipitation Method and Its Electrochemical Performance

摘要:

采用超声波沉淀法制备了不同摩尔比例Y掺杂氢氧化镍，对其粒度分布、结构及电化学性能进行了测试分析。XRD测试表明，样品均为α和β相混合结构的Ni(OH)2。激光粒度测试表明，样品均为纳米颗粒，且分布均匀，平均粒径在50~80 nm之间。分别将制备的样品以8%比例与工业用微米级球镍混合制成复合镍电极，电极的可逆性和充电效率均随Y掺杂比例增大先提高后下降，Y含量 1.17%时，其电极可逆性和充电效率达到最佳，放电比容量达到最大，0.1和0.5 C倍率下的比容量分别达到370和358 mAh/g，且具有较低充电电压和较高放电平台，该结果比目前市售镍氢电池比容量(230~250 mAh/g)高48%~60%。对加超声波和不加超声波制备的样品性能进行了比较

Abstract:

Nickel hydroxides doped with different yttrium contents were prepared by a supersonic co-precipitation method. Their particle size distribution, crystal structures and electrochemical performance were characterized. The XRD results show the co-existence of α and β phase in the nickel hydroxides. The laser particle size measurement indicates that all the samples are of nanoparticles, which are distributed uniformly with average size of 50-80 nm. Complex electrodes were prepared by mixing 8wt% nickel hydroxides with commercial micro-sized spherical nickel. The cyclic voltammetry results show that the reversibility and charge efficiency of the electrodes are increased initially and then decreased with the increase of Y content. The best reversibility and charge efficiency is observed in the electrodes with 1.17wt% Y. The discharge capacity reaches 370 mAh/g at 0.1 C and 358 mAh/g at 0.5 C for the 1.17wt% Y-doped electrodes, higher than the theoretical value of pure β-Ni(OH)2. The data is 48%-60% higher than the capacity of market Ni(OH)2 battery (230-250 mAh/g). F Furthermore, low charge potential and high discharge plateau are also observed. inally, the samples prepared under supersonic were compared with that without supersonic