School of Sustainable Engineering and the Built Environment, Arizona State University, United States; Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, United States.
Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, United States; Department of Civil and Environmental Engineering, Rice University, United States.
J Colloid Interface Sci. 2021 Dec;603:391-397. doi: 10.1016/j.jcis.2021.06.090. Epub 2021 Jun 17.
Biofouling is a major obstacle in engineered systems exposed to aqueous conditions. Many attempts have been made to engineer the surface properties of materials to render them resistant to biofouling. These modifications typically rely on passive antimicrobial or anti-adhesive surface coatings that prevent the deposition of bacteria or inactivate them once they reach the surface. However, no surface modification strategy completely prevents biofilm formation, and, over time, surfaces will be fouled and require cleaning. In this work, we demonstrate the capacity of electrochemical carbon nanotube coatings in dispersing biofilms formed on the surface. A systematic analysis of the biofilm removal kinetics in function of applied current density is made to identify the optimal current conditions needed for efficient surface cleaning. Operating the electrochemically active surface as a cathode produces superior results compared to when it is operated as an anode. Specifically, the 5.00 A m and 2.50 A m cathodic conditions produced rapid cleaning, with complete biofilm dispersal after 2 min of operation. Surface cleaning is attributed to the generation of microbubbles on the surface that scours the surface to remove the adhered biofilm. Energy consumption analyses indicate that the 2.50 A m cathodic condition offers the best combination of cleaning kinetics and energy consumption achieving 99% biofilm removal at an energy cost of ~$ 0.0318 m. This approach can be competitive compared to the current chemical cleaning strategies, while offering an opportunity for a more sustainable and integrated approach for biofouling management in engineered systems.
生物污垢是暴露于水相条件的工程系统中的主要障碍。人们已经尝试了许多方法来改变材料的表面性质，使其具有抗生物污垢的能力。这些修饰通常依赖于被动的抗菌或抗粘表面涂层，以防止细菌沉积或在它们到达表面时使它们失活。然而，没有任何表面修饰策略可以完全阻止生物膜的形成，随着时间的推移，表面会被污染，需要进行清洁。在这项工作中，我们展示了电化学碳纳米管涂层在分散表面形成的生物膜的能力。对施加电流密度的生物膜去除动力学进行了系统分析，以确定实现有效表面清洁所需的最佳电流条件。与作为阳极操作相比，将电化学活性表面作为阴极操作可产生更好的结果。具体而言，5.00 A m 和 2.50 A m 的阴极条件产生了快速的清洁效果，在 2 分钟的操作后，生物膜完全分散。表面清洁归因于表面上微泡的产生，这些微泡冲刷表面以去除附着的生物膜。能量消耗分析表明，2.50 A m 的阴极条件在清洁动力学和能量消耗方面提供了最佳的组合，在 99%的生物膜去除率下，能量成本约为 0.0318 美元/m。与当前的化学清洁策略相比，这种方法具有竞争力，同时为工程系统中的生物污垢管理提供了更可持续和集成的方法的机会。
