Abstract：
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)3/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)3/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.
摘要：
以前在用于水净化的氧化石墨烯（GO）膜的研究和开发方面取得了重大进展，但他们的生物污染行为仍然知之甚少。在这项研究中,我们在过滤天然地表水和延长运行期（110天）的情况下，研究了具有不同表面微观结构的GO膜的生物膜形成和生物污染。结果表明，相对亲水和光滑的Fe（OH）3/GO膜形成了具有高稳定通量的薄而空间异质的生物膜。然而,在弱亲水和起皱的Fe/GO和H-Fe（OH）3/GO膜中没有观察到同时减轻生物膜形成和减少生物污染的能力。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。降解有机物和捕食性细菌更适应亲水和光滑的GO表面。这些功能类群参与胞外聚合物（EPS）的降解，并改善生物膜的异质性。相比之下,弱亲水性和起皱的GO表面减少了生物多样性，同时意外地促进了EPS分泌细菌的增殖，导致生物膜形成增加和生物污染加剧。此外，所有GO膜在整个运行期间实现了可持续的水净化。
