State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
Chemosphere. 2018 Jul;202:105-110. doi: 10.1016/j.chemosphere.2018.03.065. Epub 2018 Mar 13.
The bioelectrotransformation efficiency of various organic matters and corresponding electrode biofilm community formation as well as electron transfer efficiency in bioelectrochemical systems (BESs) with different modified electrodes has been extensively studied on the anode side. However, the effects of cathode interface characteristics towards the BESs bioelectrotransformation performance remain poorly understood. In this study, the nitrobenzene-reducing biocathode catalytic efficiency and community structure in response to different modified electrodes (control: hydrophobic and no charge; -SH: hydrophobic and single negative charge; -NH: hydrophilic and single positive charge -NH-NH: hydrophilic and double positive charges) were investigated. The biocathode transformation efficiency of nitrobenzene (NB) to aniline (AN) (E) was affected by the nature of electrode interface as well as the biocathode community formation and structure. Cathodes with hydrophilic surface and positive charges have performed well in the bioelectrotransformation experiments, and especially made an outstanding performance when inorganic NaHCO was supplied as carbon source and cathode as the sole electron donor. Importantly, the hydrophilic surfaces with positive charges were dominated by the electroactive nitroaromatic reducers (Enterococcus, Desulfovibrio and Klebsiella) with the relative abundance as high as 72.20 ± 1.87% and 74.86 ± 8.71% for -NH and -NH-NH groups respectively. This could explain the higher E in the hydrophilic groups than that of the hydrophobic -SH modified group. This study provides new insights into the effects of electrode interface characteristics on the BESs biocathode performance and offers some suggestions for the future design for the improvement of bioelectroremediation performance.
在不同修饰电极的生物电化学系统（BES）阳极侧，广泛研究了各种有机物的生物电化学转化效率以及相应的电极生物膜群落形成和电子传递效率。然而，阴极界面特性对 BES 生物电化学转化性能的影响仍了解甚少。在这项研究中，研究了不同修饰电极（对照：疏水性且不带电荷；-SH：疏水性且带单一负电荷；-NH：亲水性且带单一正电荷；-NH-NH：亲水性且带双正电荷）对硝基苯还原生物阴极催化效率和群落结构的影响。硝基苯（NB）向苯胺（AN）的生物阴极转化效率（E）受电极界面性质以及生物阴极群落形成和结构的影响。具有亲水表面和正电荷的阴极在生物电化学转化实验中表现良好，特别是在无机 NaHCO3 作为碳源和阴极作为唯一电子供体时表现出色。重要的是，带正电荷的亲水表面主要由电活性硝基芳烃还原剂（肠球菌、脱硫弧菌和克雷伯氏菌）主导，相对丰度分别高达 72.20±1.87%和 74.86±8.71%。这可以解释亲水基团的 E 高于疏水性 -SH 修饰基团。本研究深入了解了电极界面特性对 BES 生物阴极性能的影响，并为未来改善生物修复性能的生物电化学修复设计提供了一些建议。
