Catalytic Activity Improvement of Carbon-Doped Bimetal–Nitrogen Using Various Sacrificial Template

The innovation of catalyst material for oxygen reduction reaction with a combination of metal precursors had been successfully synthesized using a variety of templates and post-treatment. The combination of two metal precursors consisting of transition metals (such as Fe, Ni, and Co) with the same metal ratio of 1:1 may affect the catalytic activity and physical properties. This research used 2,6-diaminopyridine as nitrogen-containing carbon material acting as a nitrogen and carbon source. This study used two types of hard templates which were LUDOX HS-40 colloidal silica and Montmorillonite K10 (MMT-K10) to optimize a dual metal with a porous nitrogen-doped catalyst. In addition, this research used a pyrolysis process at a temperature of 800 °C for 2 h within a nitrogen atmosphere. After that, post-treatment was carried out by leaching acid using a 0.5 M H₂SO₄ solution for 2 h. As a result, LUDOX HS-40 template has provided an advantage in increasing the oxygen reduction reaction (ORR) activity. In addition, the FeNi/CN-L catalyst yielded the highest catalytic activity with an electron transfer number of 3.61. LUDOX HS-40 template will make the shape of the FeNi/CN-L catalyst particles become irregular which in turn will increase ORR activity. This phenomenon is due to the electrostatic force from carbon to metal ions in which metal interactions with carbon particles occur. Thus, it can increase catalytic activity during the oxygen reduction reaction.