提高纳米TiO2在可见光下光催化及乙烯清除效果。方法 本文以FeCl3.6H2O和TiF4为原材料，采用水热合成法制备出以α-Fe2O3为核、以TiO2为壳的纳米复合型材料α-Fe2O3@TiO2，通过X射线衍射、紫外可见漫反射吸收光谱及电子顺磁共振等光化学表征及乙烯清除实验，研究其光催化和乙烯清除能力。结果 制备得到的α-Fe2O3粒子具有稳定的棒状结构，粒径长度为100~200 nm，宽度为50~100 nm;TiO2粒子为分散均匀的锐钛型空心球，直径为100~200 nm;合成的α-Fe2O3@TiO2纳米核壳球的禁带宽度降低到1.91 eV;DMPO-.O2⁻和DMPO-.OH的电子信号强度增大;具有优异的乙烯清除能力。结论 本实验制备得到的α-Fe2O3@TiO2纳米核壳球具有良好的光催化效果和乙烯清除能力，有望将其应用在果蔬保鲜中，实现杀菌、氧化分解有机物以及去除异味等功效，以达到延长货架期的目的。

The work aims to improve the photocatalytic and ethylene elimination effects of nano TiO2 under visible light. FeCl3.6H2O and TiF4 were used as raw materials to prepare a nano-composite material α-Fe2O3@TiO2 with α-Fe2O3 as the core and TiO2 as the shell by hydrothermal synthesis method. The photocatalytic performance and ethylene removal performance of the material were studied through chemical characterization means such as XRD, UV-vis DRS, EPR and ethylene removal experiments, etc. The prepared α-Fe2O3 particles exhibited a stable rod-like structure, with particle length ranging from 100 to 200 nm and width between 50 and 100 nm. The TiO2 particles exhibited hollow spheres with the diameter from 100 to 200 nm. The bandgap width of the α-Fe2O3@TiO2 core-shell nanoparticles was decreased to 1.91 eV, and the electron signal intensities of DMPO-.O2− and DMPO-.OH increased. The α-Fe2O3@TiO2 nanoparticle core-shell spheres demonstrate excellent photocatalytic performance and ethylene removal abilities, making them potential to be applied in fruit and vegetable preservation. In addition, the material is expected to own the functions of sterilization, oxidative decomposition of organic matter, and odor removal, which can extend the shelf life of fruits and vegetables.