In the search for high surface area electrodes and higher volumetric performances for bioelectrochemical systems, the use of bed electrodes has become a vital field of research. In bed electrodes, conductive particles, i.e. granules, are used as bulk material and are polarized for biofilm growth. One intrinsic constraint of bed electrodes is that these cannot be analyzed by dynamic electrochemical techniques like cyclic voltammetry (CV) due to their high internal resistance and poor polarization behavior. Therefore, solutions to elucidate the extracellular electron transfer (EET) fundamentals in bed electrodes are needed. In this study we show, using the example of a Geobacter-based bed electrode, that the thermodynamics of the EET of single granules can be revealed. This is achieved by cyclic voltammetry of single granules. A novel 3D-printed clamp working electrode is presented which can be exploited further for electrochemical analysis of biotic and abiotic electrode particles.

在寻求用于生物电化学系统的高表面积电极和更高体积性能的过程中，床电极的使用已成为重要的研究领域。在床电极中，导电颗粒（即颗粒）用作块状材料，并极化以用于生物膜生长。床电极的一个固有局限性是，由于床电极的高内阻和差的极化行为，因此无法通过动态电化学技术（如循环伏安法（CV））进行分析。因此，需要用于阐明床电极中细胞外电子转移（EET）基本原理的解决方案。在这项研究中，我们以地细菌为例进行了展示基床电极，可以揭示单个颗粒的EET的热力学。这是通过单个颗粒的循环伏安法实现的。提出了一种新颖的3D打印的钳式工作电极，该电极可进一步用于生物和非生物电极颗粒的电化学分析。