The rapid advance proton exchange membrane fuel cell technology demand highly efficient platinum based nanoscale electrocatalysts for fuel cell reactions. In this dissertation, monodisperse nanoparticles were successfully synthesized using organic solution phase synthesis methods. Not only the particle size, shape and composition were precisely controlled, but also the electronic properties of the surface atoms were finely tuned to reach the optimal catalytic performance. Moreover, Pt single crystals and sputtered thin films provide a unique insight into the structure-function relationship of the complex nanoparticle surfaces. First, pure Pt nanoparticles were used as a model catalyst to explore the best surface cleaning method for nanoparticle activation. The particle size and shape effects on oxygen reduction reaction (ORR) at fuel cell cathode were studied to optimize particle activity and stability in the ORR condition. Pt alloy nanoparticles and nanowires with Pt skin layer structure were produced with enhanced ORR activity. To minimize the Pt use, core/shell structured Au/PtM (M=Fe, Co, Cu….) nanoparticles were designed and synthesized. These core/shell nanocatalysts demonstrated tunable activities with much enhanced stability. Furthermore, Pt3Sn nanoparticles were also developed as catalyst at anode to catalyze methanol oxidation reaction (MOR). They exhibited enhanced CO tolerance and were promising next generation anode catalyst for MOR.
Li, Dongguo,
"Platinum Based Electrocatalysts for Proton Exchange Membrane Fuel Cells"
(2014).
Chemistry Theses and Dissertations.
Brown Digital Repository. Brown University Library.
https://doi.org/10.7301/Z089146C
