Electrochemical production of solar-grade silicon films from SiO2

Background

Silicon thin films are an important limitation for solar photovoltaic cells. Currently, manufacturing of these films are from single crystal silicon and a large amount of raw material is wasted. Single crystal silicon is not a cheap commodity. Thus, the sawing process used on single crystal silicon is costly not only from a manufacturing standpoint, but also through the inefficient use of raw materials.

Technology description

Researchers at The University of Texas have developed new technique method for producing photoactive silicon from silicon dioxide nanoparticles through electrodeposition in molten CaCl2. Although the choice of electrode is crucial, this process constitutes a new, less expensive process for Si-based thin film solar cells and alternative direct process for the production of silicon from cheap precursor materials.

IP Status: US Patent Grant 10,147,836

 

Figure 1: Demonstration of thin films produced from electrochemical reduction of SiO2 on different electrode substrates. Scanning electron microscopy images of Si deposited on (a) a molybdenum electrode substrate, (b) an n-type Si wafer substrate, and (c) a glassy carbon substrate. Each film shows solar grade purity from energy dispersive X-ray spectroscopy elemental analysis and is photoactive.