Enhanced electricity generation and storage by nitrogen-doped hierarchically porous carbon modification of the capacitive bioanode in microbial fuel cells

Jingxuan Wu; Ruijun Liu; Pengfei Dong; Nan Li; Weihua He; Yujie Feng; Jia Liu

doi:10.1016/j.scitotenv.2022.159688

Enhanced electricity generation and storage by nitrogen-doped hierarchically porous carbon modification of the capacitive bioanode in microbial fuel cells

Sci Total Environ. 2023 Feb 1;858(Pt 1):159688. doi: 10.1016/j.scitotenv.2022.159688. Epub 2022 Oct 24.

Authors

Jingxuan Wu¹, Ruijun Liu¹, Pengfei Dong¹, Nan Li¹, Weihua He¹, Yujie Feng², Jia Liu³

Affiliations

¹ School of Environmental Science and Engineering, Academy of Environment and Ecology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China.
² School of Environmental Science and Engineering, Academy of Environment and Ecology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, No. 73 Huanghe Road, Nangang District, Harbin 150090, China.
³ School of Environmental Science and Engineering, Academy of Environment and Ecology, Tianjin University, No. 92 Weijin Road, Nankai District, Tianjin 300072, China. Electronic address: jialiu1@tju.edu.cn.

PMID: 36302411
DOI: 10.1016/j.scitotenv.2022.159688

Abstract

Microbial fuel cells (MFCs) can potentially be utilized for power generation, but their low power density and low energy storage capabilities remain major bottlenecks for their large-scale development. In this research, a simplistic nitrogen-doped hierarchically porous carbon material (HPC-A) was developed through a one-step carbonization and activation process and was successfully hot-pressed on the carbon cloth (CC) substrate. This process fabricates capacitive bioanodes (HPC-A-CC) that can enhance electricity generation and storage in MFCs. The as-prepared HPC-A-CC anode delivered a power density of 2043.6 mW·m^-2 and a cumulative total charge (Q_m) of 426.4 ± 13.4C·m^-2 at each cycle, which was 2.1 and 34.8 times higher than that of the plain CC anode, respectively. This was a result of the hierarchical and interconnected porous structure, improved hydrophilic surface, and increased number of active centers which host the bacteria for enhanced electron transfer. Electrochemical measurements indicated the superior electrochemical activity and capacitive behavior of the HPC-A-CC anode. Furthermore, biofilm analysis revealed that the HPC-A-CC biofilm exhibited higher cell viability and a more uniform spatial distribution. These findings not only demonstrate the potential of HPC-A-CC for power enhancement in MFCs but also provide a feasible solution to the problem of power generation and demand mismatch in MFC applications.

Keywords: Capacitive anode; Electricity storage; Microbial fuel cell; Nitrogen-doped hierarchically porous carbon.

MeSH terms

Bioelectric Energy Sources*
Carbon / chemistry
Electricity
Electrodes
Nitrogen
Porosity

Substances

Carbon
Nitrogen