La^(3+)掺杂对纳米ZnO晶粒度及光催化性能的影响

Influence of La(3+)-dopant on the Gain Size and Photocatalytic Performance of Nanometer ZnO Powders

以二水合乙酸锌为原料,柠檬酸三铵为改性剂,采用溶胶-凝胶法分别制备了纯纳米ZnO粉体和La3+离子掺杂纳米ZnO粉体。XRD、TEM分析结果表明:所制得的纳米ZnO粒子均为六方晶系红锌矿结构,在热处理温度为550℃时,制得的纯纳米ZnO的晶粒尺寸最小为28.33 nm;La3+离子的掺入抑制了纳米ZnO晶粒的生长,当掺入量为0.2%时,晶粒大小减小了7 nm左右;La3+离子的掺入提高了纳米ZnO的光催化活性,比未掺杂纳米ZnO的光催化降解MB率提高了30%—40%。

Pure nanometer ZnO and La3＋ -doped nanometer ZnO were synthesized from dihydrate zinc acetate by sol-gel method. Triammonium citrate was used as modifier. The characterization of powders was studied by X-ray diffraction （XRD） and transmission dectron microscope （TEM）. The results indicated that the pattern of nano-ZnO particles all belonged to hexagonal system. When the heat treatment was at 550℃, the smallest mean particle size of nano-ZnO was only 28.33 nm. ZnO grain size became smaller with the addition of lanthanum ions, and the doping content of 0.2 % made the nanometer zinc oxide 7 nm decreased. Besides, lanthanum ion dopant increased the photocatalytic activity of nano-ZnO and the MB degradation increased by 30 %-40 %.