Optimization of bio-electrochemical systems (BESs) relies on a better understanding of electro-active biofilms (EABfs). These microbial communities are studied with a range of techniques, including electrochemical, visual and chemical techniques. Even though each of these techniques provides very valuable and wide-ranging information about EABfs, such as performance, morphology and biofilm composition, they are often destructive. Therefore, the information obtained from EABfs development and characterization studies are limited to a single characterization of EABfs and often limited to one time point that determines the end of the experiment. Despite being scarcer and not as commonly reported as destructive techniques, non-destructive visual techniques can be used to supplement EABfs characterization by adding in-situ information of EABfs functioning and its development throughout time. This opens the door to EABfs monitoring studies that can complement the information obtained with destructive techniques. In this review, we provide an overview of visual techniques and discuss the opportunities for combination with the established electrochemical techniques to study EABfs. By providing an overview of suitable visual techniques and discussing practical examples of combination of visual with electrochemical methods, this review aims at serving as a source of inspiration for future studies in the field of BESs.

生物电化学系统 (BES) 的优化依赖于对电活性生物膜 (EABfs) 的更好理解。这些微生物群落通过一系列技术进行研究，包括电化学、视觉和化学技术。尽管这些技术中的每一种都提供了有关 EABfs 的非常有价值和广泛的信息，例如性能、形态和生物膜组成，但它们通常具有破坏性。因此，从 EABfs 开发和表征研究中获得的信息仅限于 EABfs 的单一表征，并且通常仅限于决定实验结束的一个时间点。尽管比破坏性技术更稀缺，也没有像破坏性技术那样普遍报道，非破坏性视觉技术可用于通过添加 EABfs 功能及其随时间发展的原位信息来补充 EABfs 表征。这为 EABfs 监测研究打开了大门，可以补充通过破坏性技术获得的信息。在这篇综述中，我们提供了视觉技术的概述，并讨论了与已建立的电化学技术结合来研究 EABfs 的机会。通过概述合适的视觉技术并讨论将视觉与电化学方法相结合的实际示例，本综述旨在为 BES 领域的未来研究提供灵感来源。这为 EABfs 监测研究打开了大门，可以补充通过破坏性技术获得的信息。在这篇综述中，我们提供了视觉技术的概述，并讨论了与已建立的电化学技术结合来研究 EABfs 的机会。通过概述合适的视觉技术并讨论将视觉与电化学方法相结合的实际示例，本综述旨在为 BES 领域的未来研究提供灵感来源。这为 EABfs 监测研究打开了大门，可以补充通过破坏性技术获得的信息。在这篇综述中，我们提供了视觉技术的概述，并讨论了与已建立的电化学技术结合来研究 EABfs 的机会。通过概述合适的视觉技术并讨论将视觉与电化学方法相结合的实际示例，本综述旨在为 BES 领域的未来研究提供灵感来源。