Nanoscience and Nanotechnology Commons^™

Structural Evolution During Synthesis And Annealing Of Platinum-Nickel Bimetallic Nanoparticles, Xiner Lu

All Theses

In the past years, there has been an increasing interest in synthesizing Pt alloy nanocrystals to achieve high catalytic performance for energy-related applications. Pt-Ni nanoparticles (NPs) have shown high electrocatalytic activity for electrocatalysis and thermal catalysis. However, the stability of surface structures and compositions still needs to be improved to obtain better long-term catalytic stability. It is noted that thermal annealing can adjust the surface structures and compositions to improve the stability. Transmission electron microscopy (TEM) plays a vital role in characterizing the morphology, structure, and composition of nanoparticles. Specifically, the utilization of in situ TEM can allow for observing …

Investigation Of Titanium Nitride As Catalyst Support Material And Development Of Durable Electrocatalysts For Proton Exchange Membrane Fuel Cells, Bharat Avasarala

Legacy Theses & Dissertations (2009 - 2024)

The impending energy and climatic crisis makes it imperative for human society to seek non-fossil based alternative sources for our energy needs. Although many alternative energy technologies are currently being developed, fuel cell technology provides energy solutions, which satisfy a wide range of applications. But the current fuel cell technology is far from its target of large scale commercialization mainly because of its high cost and poor durability. Considerable work has been done in reducing the cost but its durability still needs significant improvement. Of the various materials in a PEM fuel cell, the degradation of electrocatalyst affects its durability …

Spectroscopic Investigation Of Palladium-Copper Bimetallic Systems For Pem Fuel Cell Catalysts, Timo Hofmann

UNLV Theses, Dissertations, Professional Papers, and Capstones

One of the main barriers to commercialization of polymer electrolyte membrane fuel cells systems is cost, which is largely due to the need of platinum (Pt)-containing catalysts. In this thesis we investigate bimetallic systems consisting of a base metal (copper) and a noble metal (palladium) that, as an alloy on the nanoscale, mimic the electronic properties that make Pt desirable as a catalyst.

We present a detailed investigation of the electronic structure of carbon-supported Pd/Cu nanoparticle catalysts, model bilayer thin film systems, alloys, and various metal reference samples. We have investigated the valence band structure of the catalysts using a …