采用以正硅酸乙酯(TEOS)水解为基础的硅溶胶种子生长法制备了粒径约为270nm的近单分散二氧化硅球型颗粒.采用一种新的溶液生长法,以氢氟酸作为溶液中镍离子配位剂,加入氨水调节溶液pH值的同时作为镍离子补充配位剂,60℃水浴条件下在已制得SiO2微球表面均匀包覆α-Ni(OH)2得到Ni(OH)2/SiO2核壳结构,Ni(OH)2壳层厚度约为35nm.结合多步包覆法提高Ni(OH)2壳层厚度,三次包覆后壳层厚度达到约100nm,四次包覆后约为140nm.采用20wt%的强碱NaOH溶液对三次包覆后的Ni(OH)2/SiO2核壳结构进行处理,得到了壳层厚度约为95nm的α-Ni(OH)2空心微球.空心微球具有较大的比表面积为141.06m2/g.
The nearly monodisperse SiO2 submicrospheres with uniform size (270nm) were prepared by the hydrolysis of TEOS. Then the SiO2 submicrospheres were coated with α-Ni (OH)2 nanoflakes by a new solution growth method. The Ni(OH) 2 nanoflakes were synthesized by a solution process using hydrofluoric acid solution as nickel ion ligand to form nickel-fluoro complex, NH3 aqueous solution as OH^- supplier and also supplemental nickel ion ligand. The coating thickness is increased with coating times. It is only 35nm for coating once. After coating three times, the coating thickness is increased to about 100nm. The α-Ni(OH)2 hollow submierospheres are obtained after subsequent removal of the core particles by NaOH solution (20wt%) at 40℃ for 24h. BET calculation shows that the surface area of the Ni(OH)2 hollow spheres is 141.06m^2/g.