Author ORCID Identifier:

https://orcid.org/https://orcid.org/0000-0002-3302-0185

Date of Graduation

8-2025

Document Type

Thesis

Degree Level

Graduate

Department

Materials Science & Engineering

Advisor/Mentor

Chen, Jingyi

Committee Member

Meng, Xiangbo

Keywords

Colloids; Electroless Deposition; Surface Chemistry

Abstract

Electroless deposition is a process that facilitates the formation of metal layers on surfaces through the reduction of metal ions onto a surface in the presence of a sacrificial reducing agent. This process can be applied to synthesize conductive metal layers on insulators such as glass or polymers. The kinetics of heterogeneous deposition depend on the interfacial surface chemistry, including the presence of added catalyst materials, as well as the bulk chemical environment, such as the concentration of metal ions and sacrificial reductants. Furthermore, the homogeneous formation of metal nanoparticles may compete with the deposition reaction, adversely affecting the control of the intended interfacial deposition. Therefore, enhancing the understanding of these reactions can improve our ability to regulate the composition and preference for heterogeneous surface electroless deposition. It is hypothesized that the occurrence of the homogeneous reaction can be limited by preventing the oxidation of the reducing agent, dimethylamine borane, and by avoiding high reactant concentrations that could lead to the formation of metal nuclei in the bulk electrolyte. The goal of this research is to identify the reaction conditions that are sufficient to promote the heterogeneous reaction while preventing the homogeneous one. This project investigates the application of UV-vis spectroscopy and gas chromatography to characterize the kinetics of both homogeneous and heterogeneous electroless reactions, examining how these reactions behave in terms of absorbance spectra and hydrogen evolution rates, respectively. Additionally, this research examines recent efforts to apply single particle tracking methods for evaluating electroless copper deposition on seeded polystyrene microspheres, with a focus on variations in reflectance and transmittance. These optical measurements are complemented by ex situ characterization techniques, such as scanning electron microscopy and energy-dispersive x-ray spectroscopy, which help calibrate optical microscopy measurements for quantitative analyses.

Download

Share

COinS