Low catalyst content remains a key requirement for the commercialization of polymer electrolyte fuel cells (PEFCs) into the energy, transportation, and material handling sectors. Understanding the fundamental phenomena reducing fuel cell performance at various stages of operation play a major role in PEFC optimization and reducing catalyst content. In this thesis, high performance PEFCs with low to moderate Pt loadings (27 - 112 μg_Pt/cm²) have been fabricated using inkjet printing. To better understand thin low Pt content electrodes the PEFCs are tested at various back pressures, relative humidity, and oxygen partial pressures. The characterized PEFCs are then simulated using OpenFCST, an open-source FEM based fuel cell simulation framework, to aid in the investigation of key performance limiting phenomena. The simulations are obtained using a macro-homogeneous, non-isothermal MEA model where a multi-step reaction kinetics describes the oxygen reduction reaction. The model is then validated against the experimental Pt loading, ionomer loading, and oxygen partial pressure study. The successfully validated model highlighted key performance limitations between low Pt content and conventional (400 μg_Pt/cm²) loading electrodes, while also highlighting the possible phenomena dictating ionomer and oxygen partial pressure performance. A mathematical model is also developed allowing the simulation of functionally graded electrodes. The model is then used to aid experimental design. To validate the new model two functionally graded ionomer electrodes are fabricated, characterized, and compared to the simulated results.