Microbial electrosynthesis (MES) shows great promise for converting CO2 into high-value chemicals. However, cathode biofilm erosion by high CO2 sparging and the unclear role of plankton in MES hinders the continuous improvement of its performance. This study aims to enhance biofilm resistance and improve interactions between bio-cathode and plankton by upgrading waste algal biomass into 3-D porous algal electrode (PAE) with rough surface. Results showed that the acetate synthesis of PAE under 20 mL/min CO2 sparging (PAE-20) was up to 3330.61 mol/m3, 4.63 times that of carbon felt under the same conditions (CF-20). The microbial loading of PAE-20 biofilm was twice that of CF-20. Furthermore, higher cumulative abundance of functional microorganisms was observed in plankton of PAE-20 (55 %), compared to plankton of CF-20 (14 %), and enhanced biocathode-plankton interactions significantly suppressed acetate consumption. Thus, this efficient and sustainable 3-D electrode advances MES technology and offers new perspectives for waste biomass recycling.

中文翻译：

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在高 CO2 喷射下使用 3-D 藻电极增强微生物电合成性能：卓越的生物膜稳定性和生物阴极-浮游生物相互作用


微生物电合成（MES）显示出将二氧化碳转化为高价值化学品的巨大前景。然而，高CO2鼓泡对阴极生物膜的侵蚀以及浮游生物在MES中的作用不明确阻碍了其性能的持续改进。本研究旨在通过将废弃藻类生物质升级为具有粗糙表面的3D多孔藻电极（PAE）来增强生物膜抵抗力并改善生物阴极与浮游生物之间的相互作用。结果表明，在20 mL/min CO2鼓泡下PAE（PAE-20）的醋酸合成量高达3330.61 mol/m3，是同等条件下碳毡（CF-20）的4.63倍。 PAE-20生物膜的微生物负载量是CF-20的两倍。此外，与 CF-20 的浮游生物 (14%) 相比，PAE-20 的浮游生物 (55%) 中功能微生物的累积丰度更高，并且增强的生物阴极-浮游生物相互作用显着抑制了乙酸盐的消耗。因此，这种高效且可持续的 3D 电极推动了 MES 技术的发展，并为废弃生物质回收提供了新的前景。