Thesis defense: Synthesis, characterization, and applications of refractory plasmonic and nanocatalyst composites

SYNTHESIS, CHARACTERIZATION, AND APPLICATIONS OF NOVEL REFRACTORY PLASMONIC AND NANOCATALYST COMPOSITES

Gehan De Silva

Department of Chemistry

New Mexico Tech

Advisor: Dr. Sanchari Chowdhury

Abstract: Plasmonic catalysts, which can absorb a broad spectrum of solar light to drive energy extensive reactions, are promising candidates to solve energy and environmental issues. Plasmonic nanoparticles can efficiently absorb visible light to generate photo excited charge carriers, which can drive catalytic reactions efficiently. However, conventional plasmonic nanomaterials like gold and silver are unstable under harsh chemical conditions and high temperatures, which are disadvantageous for industrial applications. Titanium nitride (TiN) is an alternative plasmonic material with refractory properties. Therefore, TiN based plasmonic catalysts have a huge potential for modern industry. We have enhanced the plasmonic catalytic properties of TiN by developing catalytic nanocomposite materials with TiN and transition metal catalysts (Ni and Pt).

For the synthesis of TiN-based nanocatalyst composites, we developed a visible light induced plasmon-based photodeposition method. In addition, this method requires milder conditions and simpler solution based synthetic method, which makes this process industrially feasible. The synthesized nanocomposites demonstrated a significant enhancement in catalytic properties towards photoreduction of bicarbonate to formate. We further fine-tuned the developed photodeposition method in order to achieve Ni single-atom catalysts on TiN nanoparticles. Single-atom catalysis has gained a lot of attention due to its superior specificity and efficiency. The knowledge developed here can facilitate the synthesis of other popular single-atom catalysts on plasmonic metal supports using solar light. This will open up the door to implementing single-atoms catalysts on a larger scale.

Keywords: Plasmonic nanoparticles, Nickel, Titanium Nitride, Heterogeneous catalysis, Single-atom catalsts.

Monday

September 26, 2022

12.00-1.00 PM (MDT)

Lopez 106

Zoom Link

https://zoom.us/j/99409627229
Meeting ID: 994 0962 7229