State Key Laboratory of Environmental Aquatic Chemistry, Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, People's Republic of China.
University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
Environ Sci Technol. 2024 Jul 9;58(27):12281-12291. doi: 10.1021/acs.est.4c03363. Epub 2024 Jun 28.
Significant progress has been made previously in the research and development of graphene oxide (GO) membranes for water purification, but their biofouling behavior remains poorly understood. In this study, we investigated the biofilm formation and biofouling of GO membranes with different surface microstructures in the context of filtering natural surface water and for an extended operation period (110 days). The results showed that the relatively hydrophilic and smooth Fe(OH)/GO membrane shaped a thin and spatially heterogeneous biofilm with high stable flux. However, the ability to simultaneously mitigate biofilm formation and reduce biofouling was not observed in the weakly hydrophilic and wrinkled Fe/GO and H-Fe(OH)/GO membranes. Microbial analyses revealed that the hydrophilicity and roughness distinguished the bacterial communities and metabolic functions. The organic matter-degrading and predatory bacteria were more adapted to hydrophilic and smooth GO surfaces. These functional taxa were involved in the degradation of extracellular polymeric substances (EPS), and improved biofilm heterogeneity. In contrast, the weakly hydrophilic and wrinkled GO surfaces had reduced biodiversity, while unexpectedly boosting the proliferation of EPS-secreting bacteria, resulting in increased biofilm formation and aggravated biofouling. Moreover, all GO membranes achieved sustainable water purification during the entire operating period.
在用于水净化的氧化石墨烯（GO）膜的研究和开发方面，先前已经取得了重大进展，但它们的生物污垢行为仍未得到很好的理解。在这项研究中，我们研究了在过滤天然地表水和延长运行时间（110 天）的情况下，具有不同表面微观结构的 GO 膜的生物膜形成和生物污垢情况。结果表明，相对亲水且光滑的 Fe(OH)/GO 膜形成了具有高稳定通量的薄且空间异质的生物膜。然而，在弱亲水且有皱纹的 Fe/GO 和 H-Fe(OH)/GO 膜中，并未观察到同时减轻生物膜形成和减少生物污垢的能力。微生物分析表明，亲水性和粗糙度区分了细菌群落和代谢功能。降解有机物和捕食细菌更适应亲水且光滑的 GO 表面。这些功能类群参与了细胞外聚合物（EPS）的降解，并改善了生物膜的异质性。相比之下，弱亲水且有皱纹的 GO 表面的生物多样性减少，同时出乎意料地促进了 EPS 分泌细菌的增殖，导致生物膜形成增加和生物污垢加剧。此外，在整个运行期间，所有 GO 膜都实现了可持续的水净化。
