International Islamic University, Islamabad 44000, Pakistan; Department of Chemistry and Materials Science, Aalto University, Espoo 16100, Fl-00076, Finland.
International Islamic University, Islamabad 44000, Pakistan.
J Environ Sci (China). 2021 Oct;108:107-119. doi: 10.1016/j.jes.2021.02.009. Epub 2021 Mar 2.
The promising solar irradiated photocatalyst by pairing of bismuth oxide quantum dots (BQDs) doped TiO with nitrogen doped graphene oxide (NGO) nanocomposite (NGO/BQDs-TiO) was fabricated. It was used for degradation of organic pollutants like 2,4-dichlorophenol (2,4-DCP) and stable dyes, i.e. Rhodamine B and Congo Red. X-ray diffraction (XRD) profile of NGO showed reduction in oxygenic functional groups and restoring of graphitic crystal structure. The characteristic diffraction peaks of TiO and its composites showed crystalline anatase TiO. Morphological images represent spherical shaped TiO evenly covered with BQDs spread on NGO sheet. The surface linkages of NO-O-Ti, C-O-Ti, Bi-O-Ti and vibrational modes are observed by Fourier transform infrared spectroscopy (FTIR) and Raman studies. BQDs and NGO modified TiO results into red shifting in visible region as studied in diffused reflectance spectroscopy (DRS). NGO and BQDs in TiO are linked with defect centers which reduced the recombination of free charge carriers by quenching of photoluminescence (PL) intensities. X-ray photoelectron spectroscopy (XPS) shows that no peak related to C-O in NGO/BQDs-TiO is observed. This indicated that doping of nitrogen into GO has reduced some oxygen functional groups. Nitrogen functionalities in NGO and photosensitizing effect of BQDs in ternary composite have improved photocatalytic activity against organic pollutants. Intermediate byproducts during photo degradation process of 2,4-DCP were studied through high performance liquid chromatography (HPLC). Study of radical scavengers indicated that O has significant role for degradation of 2,4-DCP. Our investigations propose that fabricated nanohybrid architecture has potential for degradation of environmental pollutions.
采用氮掺杂氧化石墨烯（NGO）纳米复合材料（NGO/BQDs-TiO）将氧化铋量子点（BQDs）掺杂的 TiO 与氮掺杂氧化石墨烯（NGO）纳米复合材料（NGO/BQDs-TiO）配对，制备出有前途的太阳照射光催化剂。它用于降解有机污染物，如 2,4-二氯苯酚（2,4-DCP）和稳定染料，即罗丹明 B 和刚果红。NGO 的 X 射线衍射（XRD）谱表明含氧官能团减少，石墨晶体结构恢复。TiO 及其复合材料的特征衍射峰显示出锐钛矿 TiO 的结晶。形貌图像表示均匀覆盖 BQDs 的 TiO 呈球形，分布在 NGO 片上。通过傅里叶变换红外光谱（FTIR）和拉曼研究观察到 NO-O-Ti、C-O-Ti、Bi-O-Ti 和振动模式的表面键合。BQDs 和 NGO 改性 TiO 导致可见光区红移，如漫反射光谱（DRS）研究所示。在 TiO 中，BQDs 和 NGO 与缺陷中心相连，通过猝灭光致发光（PL）强度来减少自由电荷载流子的复合。X 射线光电子能谱（XPS）表明，在 NGO/BQDs-TiO 中没有观察到与 NGO 中的 C-O 相关的峰。这表明 GO 中的氮掺杂减少了一些含氧官能团。NGO 中的氮官能团和三元复合材料中 BQDs 的光敏化效应提高了对有机污染物的光催化活性。通过高效液相色谱（HPLC）研究了 2,4-DCP 光降解过程中的中间副产物。自由基清除剂的研究表明，O 对 2,4-DCP 的降解起重要作用。我们的研究表明，所制备的纳米杂化结构具有降解环境污染物的潜力。
