Department of Chemical Engineering, Widener University, One University Place, Chester, PA 19013, USA.
Department of Chemistry, Widener University, One University Place, Chester, PA 19013, USA.
J Hazard Mater. 2019 Aug 15;376:178-187. doi: 10.1016/j.jhazmat.2019.05.037. Epub 2019 May 16.
We have synthesized iron oxide doped carbon nitride with 0.5 to 2 wt.% iron oxide and characterized by XPS, TGA, FTIR, SEM, photoluminescence spectroscopy and photoelectrochemical measurements. A herbicide, dicamba was employed as model organic pollutant for degradation in presence with the catalyst and hydrogen peroxide. A 3D printed photon concentrator with two chips on board (COB) LEDs with visible light spectra and two complex parabolic mirror surfaces was used as photo-reactor. The findings revealed that both photocurrent and degradation of dicamba were functions of light intensity and concentrator geometry. The rapid degradation of dicamba can be attributed to the holistic and individual actions of structural components of the photocatalyst. Four distinct phenomena, including photocatalytic activity of carbon nitride, quenching of electron/hole pairs and generation of additional reactive hydroxyl radicals by hydrogen peroxide, Fenton and photo-Fenton activity of iron oxide component of carbon nitride in presence of hydrogen peroxide and photocatalytic activity of iron oxide alone in conjuncture with carbon nitride can contribute to the overall photocatalytic activity of the system. Liquid Chromatography-Mass spectrometry (LCMS) analysis of the degradation products showed loss of chlorine from the aromatic ring and evidence of free radical addition reactions in the course of photocatalysis.
我们合成了铁掺杂氮化碳，其铁含量为 0.5 至 2wt.%，并用 XPS、TGA、FTIR、SEM、光致发光光谱和光电化学测量进行了表征。我们选择一种除草剂，即麦草畏作为模型有机污染物，在催化剂和过氧化氢的存在下进行降解。我们使用了一个带有两块 COB 发光二极管（LED）的可见光谱和两个复杂抛物线镜表面的 3D 打印光子聚光器作为光反应器。研究结果表明，光电流和麦草畏的降解均与光强度和聚光器几何形状有关。麦草畏的快速降解可归因于光催化剂结构组件的整体和单独作用。有四个不同的现象可能有助于该系统的整体光催化活性，包括氮化碳的光催化活性、电子/空穴对的猝灭以及过氧化氢产生额外的活性羟基自由基、芬顿和类芬顿反应以及过氧化氢存在下氮化碳中氧化铁成分的光催化活性，以及氮化碳与单独的氧化铁的协同光催化活性。降解产物的液相色谱-质谱（LCMS）分析表明，在光催化过程中，芳香环失去了氯，并且存在自由基加成反应的证据。
