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以γ射线辐照硫代硫酸钠和硫酸镍的混合水溶液，所得沉淀物经乙醇多次清洗后６０℃下烘干、将所得粉末样品分别在氮气氛中１６０—５００℃焙烧４ｈ，使用Ｘ射线衍射（ＸＲＤ）及扩展Ｘ光吸收精细结构（ＥＸＡＦＳ）分析样品的结构．结果表明，１６０℃以下烘于所得样品为纳米非晶，其Ｎｉ－Ｓ壳层为四配位结构，Ｎｉ—Ｓ键长为０．２２１ｎｍ．经３００℃焙烧后，非晶转变为ＮＩＳ微晶，Ｎｉ－Ｓ壳层变为八面体六配位（红镍矿型）结构，Ｎｉ—Ｓ键长增加至０２３８ｎｍ．进一步提高焙烧温度时，所形成ＮｉＳ晶粒逐渐长大，对经５００℃焙烧样品，Ｘ射线衍射检测到很尖锐的对应单一ＮｉＳ物种的衍射峰．
The mixed aqueous solution of sodium thiosulfate and nickel sulfate was irradiated with γ-rays. The resulting precipitate was washed with ethanol for several times and then dried at 60 ° C. The resulting powder samples were respectively calcined at 160-500 ° C for 4 hours in a nitrogen atmosphere, Diffraction (XRD) and Extended X-ray Absorption Fine Structure (EXAFS) were used to analyze the structure of the sample. The results show that the sample bake at 160 ℃ is nano-amorphous, and the Ni-S shell has a tetracoordinate structure with a Ni-S bond length of 0.221nm. After calcination at 300 ℃, the amorphous phase transformed into NIS crystallites. The Ni-S shell became octahedral hexagonal (red nickel type) structure and Ni-S bond length increased to 0238nm. When the calcination temperature is further increased, the NiS grains formed grow up gradually. For the samples calcined at 500 ℃, the diffraction peak corresponding to a single NiS species is sharply detected by X-ray diffraction.