Hydrogen fuel cells convert chemical energy to electrical energy with greater efficiency than traditional energy sources while having zero carbon emissions. Pt catalyst particles degrade over long operating times, resulting in decreased fuel cell performance. Nitrogen doping carbon nanotubes has been shown to increase the stability of the Pt catalyst. However, there is disagreement over which N species leads to the increased stability.

This thesis work employed a controlled synthetic approach to modify the carbon support in order to survey a wide range of N-containing molecules and determine which leads to the best stabilization of Pt nanoparticles. In our proof-of-concept study, 4-(aminomethyl)pyridine (4AMP) was covalently attached to Vulcan carbon black (VC) using organic synthesis. Pt nanoparticles were deposited and we showed the covalent functionalization of Vulcan led to small Pt nanoparticles with a narrow size distribution. In addition, cyclic voltammetry (CV) exhibited a two-fold improvement in specific current for Pt/4AMP-VC compared to Pt/VC and Pt/4AMP-VC was 4 times more durable.

Next we extended our synthetic technique to investigate the durability of Pt on amide, pyridine, pyrrole, and imidazole functionalities. X-ray photoelectron spectroscopy (XPS) suggests that Pt preferentially binds the pyridinic N in the pyridine and imidazole functionalities. Pt also strongly interacts with the pyrrolic N in the pyrrole functionality. Durability cycling 6,000 times was performed via CV and the change in Pt particle size was monitored with transmission electron microscopy (TEM). We have shown that the order of decreasing durability is imidazole > pyridine > pyrrole > amide > benzene > bare VC.

While controlled organic synthetic techniques are advantageous for comparing specific N-heterocycle molecules in the lab, this multistep procedure is not ideal for commercialization. Constant potential electrolysis was applied to easily attach 4AMP to a commercial carbon electrode and Pt was subsequently electrodeposited. Fuel cell testing demonstrated the Pt/4AMP anode generated 24 times more gravimetric power than a commercial ETEK anode.