Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin, 300387, China.
Environ Sci Pollut Res Int. 2019 Apr;26(11):11062-11073. doi: 10.1007/s11356-019-04549-9. Epub 2019 Feb 21.
In this study, reduced graphene oxide (RGO) was synthesized by -ascorbic acid reduction, which was a relatively mild and environmental friendly reduction method, and the adsorption of organic contaminants was compared to graphene oxide (GO) to probe the potential adsorption mechanisms. The morphology properties of GO and RGO were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared transmission (FTIR), Raman spectrometer, transmission electron microscope (TEM), and scanning electron microscopy (SEM). The adsorption affinities of GO and RGO for phenanthrene and 1-naphthol were studied in batch experiments. The effects of pH and surfactants were also assessed. The results demonstrated that RGO reduced by -ascorbic acid show significantly greater adsorption affinity for both phenanthrene and 1-naphthol than GO, and even greater than most of RGOs that reduced by the strong reductive reagents. This was mainly attributed to the hydrophobic interaction, π-π interaction, and H-bonding between graphene sheets and organic contaminants. Both GO and RGO showed stronger adsorption to phenanthrene than to 1-naphthol. The adsorption of 1-naphthol increased with decreasing pH and reached a maximum around pH = 7.34. The surfactants, sodium dodecyl benzene sulfaonate (SDBS) and cetyltrimethyl ammonium bromide (CTAB), had negligible influence on adsorption to GO. Note that CTAB significantly inhibited the adsorption of phenanthrene/1-naphthol on RGO, which could be attributed to the pore blockage effect. In addition, RGO could be regenerated and reused with high recyclability over five cycles. The present study suggests that RGO obtained via -ascorbic acid reduction can be deemed as a promising material for organic contaminated wastewater treatment.
在这项研究中，通过抗坏血酸还原法合成了还原氧化石墨烯（RGO），这是一种相对温和且环保的还原方法，并比较了其对有机污染物的吸附能力，以探究潜在的吸附机制。GO 和 RGO 的形貌特性通过 X 射线光电子能谱（XPS）、傅里叶变换红外透射（FTIR）、拉曼光谱仪、透射电子显微镜（TEM）和扫描电子显微镜（SEM）进行了表征。在批量实验中研究了 GO 和 RGO 对菲和 1-萘酚的吸附亲和力。还评估了 pH 和表面活性剂的影响。结果表明，用抗坏血酸还原的 RGO 对菲和 1-萘酚的吸附亲和力明显大于 GO，甚至大于用强还原剂还原的大多数 RGO。这主要归因于石墨烯片与有机污染物之间的疏水相互作用、π-π 相互作用和 H 键。GO 和 RGO 对菲的吸附均强于 1-萘酚。1-萘酚的吸附随 pH 值的降低而增加，在 pH 值约为 7.34 时达到最大值。表面活性剂十二烷基苯磺酸钠（SDBS）和十六烷基三甲基溴化铵（CTAB）对 GO 的吸附影响可以忽略不计。需要注意的是，CTAB 显著抑制了 RGO 对菲/1-萘酚的吸附，这可归因于孔堵塞效应。此外，RGO 可以通过 -ascorbic 酸还原获得，在经过五个循环后具有很高的可再生性和可重复使用性。本研究表明，通过抗坏血酸还原得到的 RGO 可被视为处理有机污染废水的一种有前途的材料。
