Non-Chemical Route to PGM-free via N+ Ion Implantation in Vertically Aligned Carbon Nanotubes.
The feasibility of a new, non-chemical methodology for synthesizing PGM-free materials based on Fe was evaluated using XPS, Raman, and electrochemistry [1]. Vertically aligned carbon nanotubes were chosen as a model material to minimize non-graphitic contributions, enabling the preparation of nitrogen-free materials adaptable to common carbon powders. By employing nitrogen ion implantation via a Kaufman ion source and Fe evaporation in a UHV chamber, surface chemistry comparable to chemical methods was achieved. XPS and Raman demonstrated the formation of N-C bonds and Fe-containing active sites without high-temperature pyrolysis. This method enhanced pyridinic N moieties crucial for stabilizing Fe-Nx sites, resulting in electrochemically active materials with improved oxygen electrocatalysis. This physics-based approach shows promise for preparing efficient N-free electrocatalysts for energy applications without extensive post-treatments.
References:
[1] V.C.A. Ficca et al Non-Chemical Route to PGM-Free via N+ Ion Implantation in Vertically Aligned Carbon Nanotubes, Adv. Funct. Mater. Doi: 10.1002/adfm.202413308
Authors: E. Placidi, V.C.A. Ficca
Magazine: Advanced Functional Material