Li Yuejin, Shang Xili, Li Changhai, Huang Xiaoming, Zheng Jingjing
College of Chemistry & Chemical Engineering, Binzhou University, Binzhou 256603, China E-mail:
Engineering Research Center for Wastewater Resource of Shandong Province, Binzhou 256603, China.
Water Sci Technol. 2018 Mar;77(5-6):1441-1448. doi: 10.2166/wst.2018.026.
Novel visible-light-induced UiO-66/BiOI photocatalysts with a p-n junction structure have been prepared for the first time through a facile hydrothermal method. The prepared photocatalysts were characterized using the powder X-ray diffraction, high resolution transmission electron microscopy, scanning electron microscopy, UV-visible diffuse reflectance spectra, and N adsorption-desorption (Brunauer-Emmett-Teller) techniques respectively. The photodegradation performances of UiO-66/BiOI photocatalysts were evaluated by photodegrading salicylic acid under visible-light irradiation. The UiO-66/BiOI composites displayed much higher photocatalytic efficiencies than pure BiOI under visible light. When the content of UiO-66 was 5.2 wt%, the composite (UiO-66/BiOI-2) has the best photocatalytic activity. Most of the salicylic acid molecules can be degraded in 100 min. The degradation rate of UiO-66/BiOI-2 samples is higher than single BiOI and UiO-66. The enhanced photocatalytic performance of UiO-66/BiOI may be ascribed to the formation of p-n heterojunctions between BiOI and UiO-66, which facilitates the transfer and separation of the photogenerated charge carriers. After recycling of the photocatalyst for five times for the photodegradation of salicylic acid, more than 85% of salicylic acid could still be degraded in the fifth cycle, implying that the as-prepared photocatalysts are highly stable.
首次通过简便的水热法制备了具有p-n结结构的新型可见光诱导UiO-66/BiOI光催化剂。分别使用粉末X射线衍射、高分辨率透射电子显微镜、扫描电子显微镜、紫外-可见漫反射光谱和N吸附-脱附（Brunauer-Emmett-Teller）技术对制备的光催化剂进行了表征。通过在可见光照射下光降解水杨酸来评估UiO-66/BiOI光催化剂的光降解性能。在可见光下，UiO-66/BiOI复合材料显示出比纯BiOI更高的光催化效率。当UiO-66的含量为5.2 wt%时，复合材料（UiO-66/BiOI-2）具有最佳的光催化活性。大多数水杨酸分子可在100分钟内被降解。UiO-66/BiOI-2样品的降解率高于单一的BiOI和UiO-66。UiO-66/BiOI光催化性能的增强可能归因于BiOI和UiO-66之间形成了p-n异质结，这有利于光生电荷载流子的转移和分离。在将光催化剂用于水杨酸光降解循环五次后，第五次循环中仍有超过85%的水杨酸可被降解，这意味着所制备的光催化剂具有高度稳定性。
