ORCID

0009-0009-7165-5163

Keywords

electrochemistry, Au nanobipyramids, thermal stability, plasmonic nanoparticles, nitrate electroreduction, localized surface plasmon resonance

Subject Categories

Chemical Engineering | Materials Science and Engineering | Nanoscience and Nanotechnology

Abstract

The development of renewable energy-conversion materials is a necessary step in the transition away from fossil fuels towards sustainable energy sources. Plasmonic Au nanobipyramids (NBPs) show promise as light-sensitizing components to facilitate the conversion of solar energy to electricity. However, their processing and application often involve elevated temperatures, which cause restructuring and a loss of their distinct plasmonic properties. Therefore, it is necessary to improve their thermal stability for robust applications. We demonstrate that the deposition of thin shells of different metals (Ag, Pd, Pt) can alter and drastically increase thermal stability. While the tips of Au NBPs and Au@Ag NBPs progressively blunt and their plasmon resonances blue-shift beginning at 100 °C, the shapes and plasmon resonances of Au@Pd and Au@Pt NBPs are well-maintained up to 200 °C and 250 °C, respectively. Notably, we also find that the shapes and plasmon resonances of Au@Pd and Au@Pt NBPs are unaffected by prolonged annealing. Electrocatalysts represent another class of renewable energy-conversion materials. Evaluation of novel electrocatalysts in academic labs is typically done in batch H-cells, which fail to replicate industrial reactors and do not provide a reliable indication of electrocatalytic performance. Using electrocatalytic nitrate reduction as a model reaction, we evaluate the performance of a nanostructured Cu foam electrocatalyst in different cell architectures: standard H-cell, recirculated flow-cell, single-pass flow-cell, and continuous-flow H-cell. While the observed performance of the Cu electrocatalyst varies with time in the H-cell and recirculated flow-cell, steady current output and product selectivity are seen in the single-pass flow-cell, emphasizing its importance for electrocatalyst screening.

Completion Date

2026

Semester

Summer

Committee Chair

Chen, Gang; Feng, Xiaofeng

Degree

Doctor of Philosophy (Ph.D.)

College

College of Sciences

Department

Chemistry

Format

PDF

Document Type

Dissertation

Language

English

Release Date

8-15-2027

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Available for download on Sunday, August 15, 2027

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