Laser driven generation of single atom Fe-N-C catalysts for the oxygen reduction reaction

Laser-assisted pyrolysis of aerosols containing phthalocyanine and pyridine yields the direct formation of Fe single atoms dispersed in nitrogen-doped carbon matrixes that can be successfully applied to the oxygen reduction reaction. • Fe-single atoms dispersed on a N-doped C network are obtained by laser pyrolysis. • Nebulization of phthalocyanines and pyridine provides an excellent precursor for SACs generation. • Thermal activation post-treatments improve the electrochemical response of Fe-N/C catalysts. • These catalysts display high ORR activity in acidic and alkaline electrolytes. Single-Atom Catalysts (SACs) have emerged as the ultimate solutions in challenging systems bridging the gap between homogeneous and heterogeneous catalysts. However, feasible synthesis methods are necessary to stabilize single metal atoms, increase catalyst loadings and scale up the synthesis. Due to its sluggish kinetics, the oxygen reduction reaction (ORR) is the main source of irreversibility in proton exchange membrane fuel cells (PEMFC). The most promising candidates to replace Pt-based catalysts for the ORR in fuel cells are the so-called Fe-N/C catalysts. These catalysts display high ORR activity in acidic and alkaline electrolytes. In this work, we propose a laser-driven pyrolysis approach to generate Fe-N/C SACs that involves decomposition of aerosolized iron-phthalocyanines. The resulting catalyst displays ORR activity in acidic and alkaline electrolytes, with competitive half-potential and kinetic current density values in comparison with state-of-the-art electrocatalysts.