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以钛酸正丁酯为前躯体,硝酸铵和九水硝酸铁为氮、铁掺杂源,利用水热法制备了氮、铁共掺杂TiO2粉体。采用XRD、FE-SEM、EDS、BET、FT-IR等手段对所制备粉体进行了表征。结果显示:共掺杂TiO2粉体为锐钛矿型,呈球状,粒径为9.2 nm,较高的比表面积201 m2/g。对甲基橙溶液的光降解实验结果表明,在350W氙灯(模拟自然光)条件下,共掺杂的TiO2对于甲基橙的降解率为96.4%,光催化活性高于P25。在太阳光下,光照4 h,对甲基橙的降解率达到84.5%。 相似文献
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《Advanced Powder Technology》2022,33(12):103859
Constructing heterojunction provides a promising tactic to improve the photocatalytic efficiency of catalysts. In this paper, hierarchical FeIn2S4/BiOBr heterostructure photocatalysts were prepared by facile two step methods and applied to effectively remove ciprofloxacin (CIP) and tetracycline (TC) under visible light. Compared to single catalyst, FeIn2S4/BiOBr hybrids display significantly improved photocatalytic activity. Among the series, 6 wt% FeIn2S4/BiOBr shows the optimal photocatalytic performance, where the degradation efficiencies of TC and CIP are 3.15 and 2.88 times greater than pure BiOBr, respectively. Such an improvement could arise from the S-scheme heterojunctions and unique hierarchical structures, which brings stronger light absorption, higher photoexcited charge separation efficiency and superior redox ability. Furthermore, 6 wt% FeIn2S4/BiOBr composite exhibits excellent stability and reusability. Radical capture experiments and EPR analyses uncover that O2–, h+ and OH are primarily reactive substances during photocatalytic removal of TC. The products of TC were detected by LC-MS analyses and possible decomposition paths are proposed. Eventually, a possible photodegradation mechanism over FeIn2S4/BiOBr S-scheme heterojunction is proposed. These findings supply new perspective for the simple synthesis of S-scheme photocatalysts with promising applications in environment remediation. 相似文献
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Geoffrey A. Ozin 《Advanced materials (Deerfield Beach, Fla.)》2015,27(11):1957-1963
While the chemical energy in fossil fuels has enabled the rapid rise of modern civilization, their utilization and accompanying anthropogenic CO2 emissions is occurring at a rate that is outpacing nature's carbon cycle. Its effect is now considered to be irreversible and this could lead to the demise of human society. This is a complex issue without a single solution, yet from the burgeoning global research activity and development in the field of CO2 capture and utilization, there is light at the end of the tunnel. In this article a couple of recent advances are illuminated. Attention is focused on the discovery of gas‐phase, light‐assisted heterogeneous catalytic materials and processes for CO2 photoreduction that operate at sufficiently high rates and conversion efficiencies, and under mild conditions, to open a new pathway for an energy transition from today's “fossil fuel economy” to a new and sustainable “CO2 economy”. Whichever of the competing CO2 capture and utilization approaches proves to be the best way forward for the development of a future CO2‐based solar fuels economy, hopefully this can occur in a period short enough to circumvent the predicted adverse consequences of greenhouse gas climate change. 相似文献
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Rohit Singh 《Particulate Science and Technology》2015,33(1):53-58
Au-modified CdS nanorods (100–200 nm × 5–10 nm) are synthesized via two different techniques, namely photodeposition and doping. The prepared samples are characterized by x-ray powder diffraction, transmission electron microscopy (TEM), and UV–vis and fluorescence spectroscopy. X-ray diffraction study confirmed the hexagonal phase of bare and Au-CdS samples, whereas, 5 wt% Au3+ doping into CdS resulted in a slight distortion in the crystal structure toward higher degree side. TEM images revealed the fine distribution of Au nanodeposits of size in the range of 2.5–4.5 nm on to the CdS surface in the photodeposited sample. The optical spectrum shows a significant red-shift in absorption onset (485 nm → 515 nm) and band-edge emission (505 nm → 512 nm) of CdS nanorods with the replacement of certain Cd2+ ions with Au3+. The influence of Au photodeposition and doping in CdS nanorods was comparatively tested by photooxidation of RhB (50 ppm) dye aqueous solution under direct sunlight irradiation (35–40 mWcm?2). Our results point out that 5 wt% Au3+ doping into CdS nanorods remarkably improved its activity and stability due to homogeneous dispersion of charge throughout the crystal, quick Fermi level equilibration, and an improvement in ionic bond formation. 相似文献
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