Bacteria-affinity aminated carbon nanotubes bridging reduced graphene oxide for highly efficient microbial...

Area of Science:

• Electrochemistry
• Environmental Science
• Materials Science

Background:

• Bioelectrochemical systems (BESs) offer dual benefits of wastewater treatment and energy generation.
• Current limitations in BES efficiency stem from electrode material resistance and poor biocompatibility.
• Developing advanced electrode materials is crucial for improving BES performance.

Purpose of the Study:

• To engineer a novel, binder-free, 3D biocompatible bioelectrode for enhanced microbial electrocatalysis.
• To improve electron transfer and bacterial colonization in BESs.
• To achieve higher current densities for efficient wastewater treatment and energy recovery.

Main Methods:

• Fabrication of a 3D bioelectrode using aminated carbon nanotubes (CNTs-NH2) and reduced graphene oxide (rGO) nanosheets.
• One-step electrodeposition technique for creating the rGO@CNTs-NH2 composite electrode.
• Performance evaluation of the novel electrode in terms of current density and microbial electrocatalytic activity.

Main Results:

• The rGO@CNTs-NH2 electrode achieved a maximum current density of 3.25 ± 0.03 mA cm⁻², a 4.33-fold increase compared to bare rGO.
• The novel electrode demonstrated superior performance, comparable to the best reported 3D electrodes.
• Enhanced electron transfer and bacterial colonization were observed due to the 3D structure, CNTs, and positive surface charge.

Conclusions:

• The developed 3D rGO@CNTs-NH2 bioelectrode significantly enhances microbial electrocatalysis in BESs.
• The binder-free, biocompatible design overcomes limitations of traditional electrode materials.
• This advancement holds promise for more efficient wastewater treatment and energy recovery applications.