Shiravizadeh A Ghorban, Yousefi Ramin, Elahi S M, Sebt S A
Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Department of Physics, Islamic Azad University (I.A.U), Masjed-Soleiman Branch, Masjed-Soleiman, Iran.
Phys Chem Chem Phys. 2017 Jul 21;19(27):18089-18098. doi: 10.1039/c7cp02995k. Epub 2017 Jul 4.
The photocatalytic properties of SnSe nanostructures (NSs) and SnSe/graphene nanocomposites with different graphene concentrations (5, 10, and 15 wt%/v) were investigated. The products were synthesized by a simple and cost-effective co-precipitation method. The samples obtained demonstrated that graphene concentration at an optimum amount was an important factor in enhancing the photocatalytic performance of the products. The graphene source was graphene oxide (GO) sheets and several characterization results indicated, which were used to remove Methylene blue (MB) dye, that the GO sheets were changed into reduced graphene oxide (rGO) sheets during the synthesis process. The optical properties of the products were studied using a room temperature photoluminescence (PL) spectrometer and it was observed that the near-band-edge (NBE) position of the samples was at the end of the red region between 729 and 756 nm of the electromagnetic spectrum, which was confirmed by a UV-vis spectrometer. The PL spectra of the samples also demonstrated three emissions from the violet, green, and orange regions of the visible spectrum, which were from different defects. The samples were annealed in a hydrogen and air atmosphere at 300 °C and it was found that defect concentrations were increased by annealing for the SnSe/rGO nanocomposites. The photocatalyst studies of the post-annealed samples revealed that the photocatalytic performance of the products was enhanced by annealing in hydrogen, while it was reduced by annealing in air. In addition to MB, the photocatalytic performance of the products for the degradation of phenol as a colorless pollutant was examined. It was observed that rGO in this process also had a significant role in the enhancement of photocatalytic performance. In fact, the electron spin resonance (ESR) test showed the role of rGO in photocatalytic activity very well.
研究了具有不同石墨烯浓度（5、10和15 wt%/v）的SnSe纳米结构（NSs）和SnSe/石墨烯纳米复合材料的光催化性能。通过一种简单且经济高效的共沉淀法合成了这些产物。所获得的样品表明，最佳量的石墨烯浓度是提高产物光催化性能的一个重要因素。石墨烯源为氧化石墨烯（GO）片，几个表征结果表明，在合成过程中GO片转变为还原氧化石墨烯（rGO）片，这些样品用于去除亚甲基蓝（MB）染料。使用室温光致发光（PL）光谱仪研究了产物的光学性质，观察到样品的近带边（NBE）位置在电磁光谱729至756 nm的红色区域末端，这通过紫外可见光谱仪得到了证实。样品的PL光谱还显示了来自可见光谱的紫色、绿色和橙色区域的三种发射，它们来自不同的缺陷。在300°C的氢气和空气气氛中对样品进行退火处理，发现对于SnSe/rGO纳米复合材料，退火会增加缺陷浓度。对退火后样品的光催化剂研究表明，在氢气中退火可提高产物的光催化性能，而在空气中退火则会降低其光催化性能。除了MB，还考察了产物对作为无色污染物的苯酚降解的光催化性能。观察到在此过程中rGO在提高光催化性能方面也起着重要作用。事实上，电子自旋共振（ESR）测试很好地显示了rGO在光催化活性中的作用。
