Project Description

Project Overview:  Silicon is a commonly used photo-electrochemical material due to its band gap, carrier intrinsic concentration, and doping capabilities. However, it faces drawbacks such as charge recombination and surface corrosion in extreme pH environments and during electrochemical reactions. Introducing a conductive and chemically inert protective layer such as TiO2 can help stabilize the photo-electrode and increase its lifetime. Atomic layer deposition (ALD) is used to apply this oxide, because it has precise thickness control, good surface conformity, and controllable crystallinity. When depositing the protective coating, an undesirable, metastable, intermediate phase can form. The goal of this project is to find the optimal temperature of ALD TiO2 film synthesis to suppress this intermediate phase. The team will characterize the films using SEM, XPS, and AFM, as well as perform photo-electrochemical tests to evaluate the quality of oxide films.

 Client:  Dr. Xudong Wang, Department of Materials Science and Engineering University of Wisconsin-Madison

Student Team:  Katherine Koets, Emily Guesneau, Nicole Wong, Jenna Hemenway