Highly Active and Durable Transition Metal-Coordinated Nitrogen Doped Carbon Electrocatalyst for Oxygen Reduction Reaction in Neutral Media

Abstract

The major technical obstacles in commercialization of microbial fuel cell technology are the sluggish kinetic, high cost, and poor durability of an air cathode electrocatalyst. This research aimed to synthesize the highly active, stable and low cost non-precious metal catalyst to replace the expensive Pt electrocatalyst using a simple, low cost and scalable method. The Fe3C and Fe-N-C catalysts were prepared by direct heating the precursors under autogenic pressure conditions. X-ray diffraction pattern revealed the phase of Fe3C sample was cohenite Fe3C and graphitic carbon, while the phase of Fe-N-C catalyst was only graphitic carbon. The morphology of the synthesized catalysts was a highly porous structure with nanoparticle morphology. The surface area of the Fe3C and the Fe-N-C catalysts was 295 and 377 m2 g-1, respectively. The oxygen reduction reaction (ORR) activity of Fe-N-C catalyst was more active than Fe3C catalyst. The ORR performance of Fe-N-C catalyst exhibited about 1.6 times more superior to that of the noble Pt/C catalyst. In addition, the Fe-N-C catalyst was durable to operate under neutral media. Thus, a novel autogenic pressure technique was a promising method to effectively prepare an highly active and durable non-precious metal catalyst to replace the precious Pt/C catalyst.

Nanostructured Fe-N-C as Bifunctional Catalysts for Oxygen Reduction and Hydrogen Evolution

“…However, low availability and high cost of PGM catalysts limits a commercial application for the MFC and electrolyzes devices, requiring low cost and earth abundant materials [5]. The development of catalysts based on PGM-free materials was indeed pursued by the electrocatalyst community, demonstrating that PGM-free catalysts can be an alternative to Pt due to their high activity in acid and alkaline environment and good durability towards both ORR and HER [1,[7][8][9][10][11][12][13].…”

N and S Dual-Doped Mesoporous Carbon Nanostructure as a High Performance and Durable Metal Free Oxygen Reduction Reaction Electrocatalyst

“…SEM image clearly reveals uniform nanosized particle connected chain-like structure which is a unique characteristic morphology of VXC 72R. The particle size was approximately in the range of 30-50 nm [21,23]. In addition, the prepared NS-VXC sample exhibited noticeably high porosity which has benefit in the facile diffusion of reactant and product through the sample.…”

“…The reference Ag/AgCl potential was converted to the reversible hydrogen electrode (RHE) potential following the equation reported in the literature [19]. The catalyst ink with the composition of 5 mg catalyst, 250 μL of DI-water, 20 μL of Nafion (5%), and 500 μL of isopropyl alcohol was ultrasonically dispersed for 30 min to obtain a homogenous ink [20][21][22]. The homogeneous ink was then carefully coated onto a clean RRDE electrode and left it dry under room temperature.…”

Flexible doctor blade-coated abiotic cathodes for implantable glucose/oxygen biofuel cells

“…Graphene is used for both the anodic and cathodic materials, showing excellent performances on either glucose oxidation or oxygen reduction. 17 Most of the graphene-based abiotic catalysts were tested in basic media, and only a few investigations in neutral media were done 18,19 . Newly, Su et al 20 fabricated a nonenzymatic glucose fuel cell using graphene sheets graed with platinum and palladium for glucose oxidation and nitrogendoped graphene oxide for oxygen reduction.…”