A new modification method of metal substrates via candle soot to prepare effective anodes in air‐cathode microbial fuel cells

Abstract

BACKGROUND: Choosing applicable anodes can effectively promote the performance of microbial fuel cells (MFCs). This study introduced a novel method to prepare effective metal-based anodes modified by carbon nanoparticles (CNPs) derived from candle soot. The CNPs can be firmly coated on the metal and the modified metal surfaces show good hydrophilicity.RESULTS: This study used titanium mesh, stainless steel sheet and copper sheet as the anode's substrate, respectively. CNPs could improve the biocompatibility and electrochemical properties of these metals. The power generation performance of MFCs with CNP-modified anodes has been dramatically enhanced, and the maximum power density is 616 mW m −2 in MFCs with CNP-modified titanium mesh anode.CONCLUSION: After CNP modification, the rough surface and excellent biocompatibility could promote the attachment and growth of microorganisms, which may be the main reasons for the improvement of MFC performance. Besides, this method is suitable to modify different metal substrates. The results showed that the CNP-coated metal anodes could improve the power output of MFCs compared to pure metal anodes. Therefore, this method has significant advantages in the practical application of MFCs.

Microbe–Anode Interactions: Comparing the impact of genetic and material engineering approaches to improve the performance of microbial electrochemical systems (MES)

“…To overcome this issue, MnO 2 was deposited on multi‐walled carbon nanotubes, resulting in a 112‐fold increase in power density to about 0.4 W m −2 . Moreover, Pu et al ( 2022 ) used a rather impressive method to deposit carbon nanoparticles for the modification of titanium mesh, stainless steel and copper sheets. Carbon nanoparticles derived from candle soot were already utilized in MFCs on stainless steel electrodes by Singh, Bairagi, and Verma ( 2018 ), but the deposition led to uneven layers of carbon nanoparticles that easily detached from the modified material.…”

“…Carbon nanoparticles derived from candle soot were already utilized in MFCs on stainless steel electrodes by Singh, Bairagi, and Verma ( 2018 ), but the deposition led to uneven layers of carbon nanoparticles that easily detached from the modified material. Thus, Pu et al ( 2022 ) used a series of flame deposition, surface paraffin combustion, and heat treatment to achieve uniform deposition of carbon nanoparticles. Flame deposition coated the material with carbon nanoparticles, while paraffin combustion bound the layer tightly to the surface.…”

“…If both technical and genetic optimization can each achieve higher power and energy yields, it can be hypothesized that a combination would lead to even better performances. For example, as described above, a S. oneidensis mutant strain overexpressing speC (Edel et al, 2021 ) colonizing a titanium network to which carbon nanoparticles have been deposited (Pu et al, 2022 ) would be a conceivable approach for enhancing performance even further. All of the scenarios described are intended to illustrate that MES research must become multidimensional and multidisciplinary so that different perspectives can be considered.…”