TiO_2-Ti_3C_2 Composites with Pt Decoration as Efficient Photocatalysts for Ethylene Oxidation under Near Infrared Light Irradiation

Efficient utilization of solar energy is highly desirable in the field of photocatalysis. However, the near-infrared part of the solar spectrum, which constitutes about 44% of sunlight, has rarely been used. Herein, we report that the TiO_2 coupled with MXene Ti_3C_2 nanosheets shows promising photoactivity for ethylene oxidation under near infrared light(NIR) irradiation. Moreover, the Pt nanoparticle decoration can dramatically improve the performance of TiO_2–Ti_3C_2 nanocomposites. Within 15 minutes irradiation of the NIR light, 444 ppm of C_2 H_4 is completely removed over 1 wt%Pt–TiO_2–Ti_3C_2 and the catalyst exhibits excellent stability. It is expected that our work could provide useful information for the design and synthesis of efficient and stable NIR active photocatalyst for the target applications.     

Controllable Synthesis,Polar Behavior and Photoelectric Properties of BiOCl Microplates

Bismuth oxychloride（BiOCl） square microplates were prepared via a facile hydrothermal method. The X-ray diffraction patterns of the samples reveal a tetragonal BiOCl phase, and the scanning electron microscopy images show plate-like structures with large lateral size of 3～6 μm and thickness in the range of 100～300 nm. The effects of surfactant, reaction temperature and duration on the morphology of BiOCl powders are systematically investigated. The polar behavior of a BiOCl single-crystalline mi...     

Fabrication of WO_3/TiO_2 Heterostructures for Efficiently Photocatalytic Gaseous Hydrocarbons Degradation: Origin of Photoactivity and Revisit the Role of WO_3 Decoration

Efficient oxidation of gaseous small molecular hydrocarbons under mild conditions remains a significant but challenging task to date.Here we report that WO_3 decoration can obviously improve the performance of Ti O_2(P25)toward the photocatalytic oxidation of several small molecular hydrocarbons(C_2H_6,C_3H_8 and C_2H_4)under simulated solar light irradiation.Among the WO_3/Ti O_2 heterostructures,the 10wt%WO_3/Ti O_2 nanocomposite shows the best photoactivities,which can efficiently oxidize C_2H_6,C_3H_8 and C_2H_4 within 15,9 and 8 minutes,respectively under simulated sunlight with a light intensity of 200 m W/cm~2.By strong contrast,a decreased photoactivity of Ti O_2 by coupling with WO_3 is observed when investigating the performance of photocatalysts toward the degradation of methylene blue(MB)in liquid phase.The opposing effect of WO_3 decoration on the performance of Ti O_2 is thoroughly investigated,and it is found that the improved photoactivities for gaseous hydrocarbon degradation is ascribed to the enhanced oxygen adsorption,resulting from WO_3 decoration rather than efficient charge separation within the WO_3/Ti O_2 heterostructures.     

BiVO4晶体的坩埚下降法生长与性能研究

采用坩埚下降法成功生长出厘米尺寸的单斜相BiVO4晶体并利用X射线衍射仪、偏振光显微镜、接触角测量仪和静电计对其结晶形态、表面畴结构、接触角随光照时间的变化以及电阻率随温度的变化行为进行了研究.发现BiVO4晶体接触角随光照时间呈现先减小后增大的变化规律,同时电阻率随温度升高呈现先增大后减小的正温度系数效应.