利用溶胶-凝胶法制备掺杂铜、锌和铁离子的复合纳米TiO₂，采用冷冻干燥和高温干燥2种方法处理纳米溶胶获得纳米抗菌微粉。模拟自然状态下，采用菌丝抑制率法进行抑菌特性实验，统计病原菌存活数、相对抑菌率，鉴定TiO₂的抗菌活性。对制备的溶胶材料进行XRD和TEM等物性表征，结果表明，材料的晶型均为锐钛型，外形如梭子般，颗粒的粒径分布范围在20~90 nm之间。获得的微粉由于掺入的金属离子不同而呈现不同的颜色，掺锌为乳白色，掺铜为淡蓝色，掺铁为浅绿色。抑菌能力与掺杂量有关，掺杂样品抑菌能力均高于无掺杂样品，3种金属离子掺杂质量分数为0.4%时表现出较好的抑菌效果，不同植物病原菌抑菌实验表现都如此。经过冷冻干燥处理的样品的抑菌活性稍强于高温焙烧处理，对于病原菌均有抑制作用，效果差异不显著。6种病原菌对实验的无机抗菌剂较为敏感的是黄瓜枯萎菌，抑制率达到65%左右，较低的是红枣链格孢菌，抑制率为41%；制备的纳米抗菌剂具有广谱性。

Nanocomposite TiO₂ doped with copper,zinc and iron ions respectively is prepared by sol-gel method and is then handled by freeze drying method and high temperature drying method respectively to obtain two kinds of nanoscale antibacterial micro-powders.Under the simulated natural conditions,the inhibition rate of mycelium is used to test the antibacterial characteristics.The antibacterial activity of TiO₂ is determined by counting the survival rate of pathogenic bacteria and relative antibacterial rate.The sol material prepared are characterized via XRD and TEM,and the results exhibit that the crystalline types of materials are all anatase and of fusiform,with particle size distribution in the range of 20-90 nm.The obtained micro powder exhibit different colors according to different metal ions doped.The powder doped by zinc is milky white,that doped by copper is light blue,and that by iron is light green.The antibacterial ability has relation to the dosage amount.The doped samples have higher antibacterial ability than non-doped samples.Good antibacterial effects can be achieved when the doping amounts of 3 kinds of metal ion are 0.4% each,and the same results can be gained even if tests are performed upon different plant pathogenic bacteria.The antibacterial activity of samples that is handled by frozen drying method is slight stronger than that of the samples handled by high temperature drying method.Both kinds can inhibit the pathogenic bacteria without significant difference in effect.Among six pathogenic bacteria,the pathogenic bacterium of cucumber fusarium wilt is the most sensitive to the experimental inorganic antibacterial agent samples,with an inhibition rate of about 65%,and Alternaria sp.is the lowest,41%.It is verified that the nano antibacterial agent prepared by this method has broad spectrum.

马超(1989-),男,硕士研究生,研究方向为抗菌材料制备及其性能研究,10639059@qq.com