Polyaniline-Derived Nitrogen-Containing Carbon Nanostructures with Different Morphologies as Anode Modifier in Microbial Fuel Cells

Abstract

Anode modification with carbon nanomaterials is an important strategy for the improvement of microbial fuel cell (MFC) performance. The presence of nitrogen in the carbon network, introduced as active nitrogen functional groups, is considered beneficial for anode modification. In this aim, nitrogen-containing carbon nanostructures (NCNs) with different morphologies were obtained via carbonization of polyaniline and were further investigated as anode modifiers in MFCs. The present study investigates the influence of NCN morphology on the changes in the anodic microbial community and MFC performance. Results show that the nanofibrillar morphology of NCNs is beneficial for the improvement of MFC performance, with a maximum power density of 40.4 mW/m2, 1.25 times higher than the anode modified with carbonized polyaniline with granular morphology and 2.15 times higher than MFC using the carbon cloth-anode. The nanofibrillar morphology, due to the well-defined individual nanofibers separated by microgaps and micropores and a better organization of the carbon network, leads to a larger specific surface area and higher conductivity, which can allow more efficient substrate transport and better bacterial colonization with greater relative abundances of Geobacter and Thermoanaerobacter, justifying the improvement of MFC performance.

Nanocomposite use in MFCs: a state of the art review

“…Polyaniline (PANI), a nitrogen-containing polymer, has been extensively used for electrochemical energy production and storage due to its simple synthesis, excellent environmental stability, cheap manufacturing cost, and high nitrogen content. 118–120 The positive charges given by the nitrogen atoms present on the surface of PANI increase the adhesion of the electroactive biofilm and enhance EET. 121 For this reason, the physical structure of PANI has been modified to optimise the surface area and pore size, providing an anode with optimal features and increased MFC performance.…”

Electrochemical Biosensing of L-DOPA Using Tyrosinase Immobilized on Carboxymethyl Starch-Graft-Polyaniline@MWCNTs Nanocomposite

“…In the spectrum of PANI, a wide band at 3402 cm −1 results from N-H stretching vibrations in the aromatic amine [27]. Two peaks around 1560 cm −1 and 1480 cm −1 are due to the stretching vibration of C=N and C=C in the benzenoid and quinoid moieties in the PANI chains [28]. In the spectrum of CMS-g-PANI@MWCNTs, interactions between OH and N-H groups from the CMS and PANI, respectively, caused a change in intensity and peak position at 3432 cm −1 [26].…”

Pt-Based Nanostructures for Electrochemical Oxidation of CO: Unveiling the Effect of Shapes and Electrolytes

“…A worldwide squeeze on traditional non-renewable energy resources not only generated crippling deficiencies and surging fuel prices but also increased the carbon footprint [ 1 , 2 , 3 , 4 ]. The promising solutions are finding renewable energy resources [ 5 , 6 , 7 , 8 , 9 , 10 ] and gas conversion to high value-added products [ 1 , 2 , 3 , 4 ]. Electrochemical energy conversion and production technologies, such as alcohol fuel cells are considered eco-friendly, efficient, and sustainable energy sources due to their zero-emissions, outstanding power density, earth-abundance of alcohols, and low-operation temperature [ 11 , 12 , 13 ].…”