The microbial fuel cell (MFC) efficiency was assessed by using biochar electrode. Electrodes were made of silicon (Si_0.4), zinc (Zn_0.4), and copper (Cu_0.4) in 40% proportions mixed with derived waste coconut shell (CS) biochar materials after the carbonization process. The specific surface area of CS-Si_0.4 (0.1920 m² g⁻¹), CS-Zn_0.4 (0.2025 m² g⁻¹), and CS-Cu_0.4 (0.2532 m² g⁻¹) is higher when compared to Graphite Particle (GP) (0.2165 m² g⁻¹). Electrodes’ power production outputs were CS-Si_0.4 ((19.22 ± 0.5) mW m⁻²), CS-Zn_0.4 ((26.40 ± 0.6) mW m⁻²), and CS-Cu_0.4 ((47.04 ± 0.5) mW m⁻²) similar to GP ((32 ± 0.5) mW m⁻²). Experimental results show that the CS-Cu_0.4 electrode provides maximum power output and efficiency. The inclusion of metals will increase surface area of biochar electrodes, and it increases the microbial fuel cell efficiency. The CS-Cu_0.4 electrodes are therefore feasible, biocompatible, and cost-effective for environmentally sustainable systems.

Graphical abstract

中文翻译：

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废生物质衍生碳电极对微生物燃料电池性能的增强研究

通过使用生物炭电极评估微生物燃料电池（MFC）的效率。碳化后，电极以40％的比例由硅（Si _0.4），锌（Zn _0.4）和铜（Cu _0.4）与衍生的废椰子壳（CS）生物炭材料混合而成。与石墨相比，CS-Si _0.4（0.1920 m ² g ^-1），CS-Zn _0.4（0.2025 m ² g ^-1）和CS-Cu _0.4（0.2532 m ² g ^-1）的比表面积更高颗粒（GP）（0.2165 m ² g ^-1）。电极的发电量为CS-Si _0.4（（19.22±0.5）mW m ^-2），CS-Zn _0.4（（26.40±0.6）mW m ^-2）和CS-Cu _0.4（（47.04±0.5）mW m ^-2）类似于GP（（32±0.5）mW m ^-2）。实验结果表明，CS-Cu _0.4电极可提供最大的功率输出和效率。金属的夹杂物将增加生物炭电极的表面积，并增加微生物燃料电池的效率。因此，CS-Cu _0.4电极对于环境可持续的系统而言是可行的，生物相容的且具有成本效益。

图形概要