Microbial electrosynthesis (MES) is an emerging technology through which autotrophic microorganisms can directly uptake electrons or indirectly uptake electrons through H₂ in the cathode for reducing CO₂ to chemicals. In this study, the performance of MES with engineered Clostridium ljungdahlii was improved by electrochemically depositing a nickel phosphide (Ni–P) catalyst on the cathode. The acetate production rate of MES with 15 cycles was 0.17 g L^–1 day^–1, which was 1.7 times higher than that of MES without the catalyst. The corresponding butyrate production rate was remarkably enhanced at 0.1 g L^–1 day^–1, which was 2.5 times higher than that of MES without the catalyst. Electrochemical studies, scanning electron microscopy, and confocal scanning laser microscopy showed that Ni–P could accelerate the release of hydrogen and promote biofilm formation. These results also implied that more H₂ evolution could provide more reducing power for butyrate production in the presence of Ni–P. This study attempted to provide effective strategies for the accumulation of C₄ products in MES.

中文翻译：

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涉及工程化的钟氏梭状芽胞杆菌与磷化镍修饰的电极的CO ₂还原反应增强乙酸和丁酸的微生物电合成

微生物电合成（MES）是一种新兴技术，通过该技术，自养微生物可以直接吸收电子或通过阴极中的H ₂间接吸收电子，以将CO ₂还原为化学物质。在这项研究中，通过在阴极上电化学沉积磷化镍（Ni-P）催化剂，改进了工程化的梭菌梭状芽胞杆菌的MES性能。15个循环的MES的乙酸盐产率为0.17 g L ^–1天^–1，是不使用催化剂的MES的1.7倍。相应的丁酸酯生产率在0.1 g L ^–1天^–1时显着提高，是没有催化剂的MES的2.5倍。电化学研究，扫描电子显微镜和共聚焦扫描激光显微镜显示，Ni-P可以加速氢的释放并促进生物膜的形成。这些结果还暗示，在Ni-P存在下，更多的H ₂释放可为丁酸生产提供更多的还原能力。这项研究试图为在MES中积累C ₄产物提供有效的策略。