I-III-VI2 (Copper Chalcopyrite-based) Materials for Use in Hybrid Photovoltaic/Photoelectrochemical Water-Splitting Devices.

摘要

This project, in an effort to improve upon basic crystalline silicon photovoltaic energy conversion, proposes both an alternative material and an alternative method of solar energy conversion.;The sun, responsible for giving us life of all kinds, is capable of giving us more. Photovoltaic energy, derived from the conversion of solar energy to electrical energy, can be a very efficient process. Unfortunately, it is often produced at a location and time where we are unable to use it immediately, necessitating transmission or storage of this converted energy; both imposing energy losses and costs. Furthermore, the typical use of crystalline silicon for this process is hindered by supply and fabrication cost issues.;Photoelectrochemical (PEC) water-splitting offers an alternative energy-transport mechanism in the form of evolved hydrogen gas. Untethered by aging power lines and insufficient energy distribution technology, hydrogen gas offers new methods to store and transport converted solar energy to be used in fuel cells or hydrogen combustion engines representing a sustainable, clean and completely carbon-free energy cycle.;PEC water-splitting also allows the use of a variety of new semiconductor materials like the I-III-VI2 copper chalcopyrite based material class capable of displacing our reliance on crystalline silicon used to harness the sun's power. Capable of photocurrents as high as 20mA/cm 2, a device utilizing this material demonstrates 4.35% solar-to-hydrogen conversion efficiency. Material durability is also documented, achieving 420 hours of sustained water-splitting representing 4.6 years of operation.