电沉积法制备镍-63放射源工艺研究

Study on Preparation Process of Ni-63 Radioactive Sources by Electrodeposition

微型核电池用镍-63放射源要求放射源表面发射率高、镀层薄、衬底小,以小体积、高比活度、低镍浓度的镍-63溶液作为电沉积液,建立一种直流恒流电沉积制备镍-63放射源的方法。采用该方法,衬底为紫铜材质、Ni^(2+)浓度为1 g/L、电沉积液pH为3.5~4.5、氨基磺酸浓度为0.1 g/L条件下电沉积1 h,电沉积率可达95.8%。制备的镍-63放射源源片镀层紧密、光亮,厚度0.3~1.6μm,其表面发射率最高可达2.40×10^(7)s^(-1)·(2πSr)^(-1),活度最高可达1.89×10^(9)Bq,满足微型核电池的应用需求。同时,通过对剩余电沉积液进行回收、组分调节,实现了电沉积液的重复利用,减少了镍-63原料的浪费。

Nickel-63 radioactive sources used in micro nuclear batteries require high surface emissivity,thin coating and small substrate.The method for the preparation of nickel-63 radioactive sources by direct and constant current electrodeposition was established by using nickel-63 solution with small volume,high specific activity and low Ni^(2+)concentration as electrodeposition liquid.Using this method,under the conditions of copper substrate,Ni^(2+)concentration with 1 g/L,electrodeposition pH with 3.5-4.5 and sulphamic acid concentration with 0.1 g/L,the electrodeposition efficiency can reach to 95.8%after 1 h.The coating is compact and bright with the thickness from 0.3μm to 1.6μm.The surface emissivity of the prepared nickel-63 radio-source film is up to 2.40×10^(7)s^(-1)·(2πSr)^(-1) while the activity is up to 1.89×10^(9)Bq,which can meet the application requirements of micro nuclear batteries.At the same time,by recovering the residual electrodeposition solution and adjusting its composition,the reuse of electrodeposition liquid is realized,reducing the waste of nickel-63 raw material.