Antibacterial Activity of Grophene Oxide/g-C3N4 Composite through Photocatalytic Disinfection under Visible Light
Antibacterial Activity of Grophene Oxide/g-C3N4 Composite through Photocatalytic Disinfection under Visible Light
复制标题
氧化石墨烯/g-C3N4复合材料可见光下光催化消毒的抗菌活性
DOI：
10.1021/acssuschemeng.7b01431
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发表时间：
2017
影响因子：
8.4
通讯作者：
Han Heyou
中科院分区：
文献类型：
--
作者：
Sung Long;Du Ting;Hu Chao;Chen Juanni;Lu Jian;Lu Zhicheng;Han Heyou
碳基纳米材料由于具有高比表面积、极高的机械强度和独特的物理化学性质等优点，已被广泛开发为新型抗菌剂。本文采用室温超声法制备了氧化石墨烯/碳氮化石墨烯纳米复合材料(GO/g-C3N4)，并对其抗菌性能进行了研究。100μg/mLGO/g-C3N4复合材料对E的杀灭率为97.9%。经120分钟可见光照射后，用荧光细胞膜完整性检测进一步证实。此外，电子自旋共振(ESR)谱和捕获实验证实，光催化产生的空穴是参与光催化杀菌的主要活性物种，并通过透射电子显微镜和扫描电子显微镜进一步证实，光催化产生的空穴导致细胞膜的变形和破裂，最终导致细胞死亡。进一步的光致发光(PL)、循环伏安、光电流产生和交流阻抗(EIS)表征表明，GO的引入有助于分离光生电子，阻止g-C3N4的电子-空穴对重组产生更多的h+，从而直接提高GO/g-C3N4的杀菌能力。可重用性分析表明，GO/g-C3N4在4次循环使用后仍保持90%以上的活性。这项研究有助于深入了解可见光驱动消毒的机理，并为处理微生物污染的水提供了一种理想的候选灭菌剂。
Carbon-based nanomaterials have been widely developed into innovative antimicrobial agents due to their advantages of high surface-to-volume ratio, extremely high mechanical strength, and distinct physicochemical properties. Here, the nanocomposite of graphene oxide/graphitic carbon nitride (GO/g-C3N4), a free-metal photocatalyst, was fabricated through sonication at room temperature and its antibacterial activity againstEscherichia coli(E. coli) was investigated. The 100 μg/mL GO/g-C3N4composite was found to kill 97.9% ofE. coliafter 120 min visible light irradiation, which was further confirmed by fluorescent-based cell membrane integrity assay. Additionally, the holes produced by photocatalysis were confirmed by electron spin resonance (ESR) spectra and trapping experiments to participate in photocatalytic sterilization as principal active species and were further verified by transmission electron microscopy (TEM) and scanning electron microscope (SEM) to lead to the distortion and rupture of cell membrane and finally cell death. Further photoluminescence (PL) spectra, cyclic voltammetry, photocurrent generation, and impedance spectroscopy (EIS) characterization revealed that the introduction of GO contributed to separate photogenerated electrons and prevents the electron–hole pairs of g-C3N4from recombing to generate more h+, thus directly improving the bactericidal ability of GO/g-C3N4. Reusability assays indicated that the GO/g-C3N4retained more than 90% of activity after four cycles of use. This study facilitates an in-depth understanding of the mechanism of visible light-driven disinfection and provides an ideal candidate sterilizing agent for treating microbial-contaminated water.