There is an immediate need to find renewable and sustainable energy sources that can replace fossil fuels. The Sun provides an enormous amount of energy that can easily surpass the global energy demand by more than an order of magnitude. However, solar energy needs to be stored in a robust way in order to use energy on demand when the sun is not shining. Solar water splitting has shown to be an efficient way to convert solar energy into chemical energy, when water is broken down into its principle components, oxygen and hydrogen. Hydrogen can be used as a clean alternative to fossil fuels without emitting any CO2, and thus solar water splitting offers a long-term solution to the global energy needs, while maintaining a clean environment. In addition, using CO2 as a feedstock to synthesize highly valuable chemicals and fuels also can also help to reduce our growing atmospheric CO2 concentration. The main goal of the Smith lab is to understand and optimize materials that can be used for the conversion of solar energy into chemical fuels via (1) Direct solar to fuel conversion via photoelectrochemistry, (2) Solar to electrical energy conversion via photovoltaics, and (3) electrical to chemical energy conversion via electrocatalysis. Within these themes, the raw materials used are sunlight, water and CO2.
Directly converting solar energy into chemical fuels has the potential to be a game-changing technology to help store the immense and limitless power of the Sun. Our work focuses on materials synthesis and characterization of semiconductor photoelectrodes to identify and overcome their limitations. See more on the photoelectrochemistry page.
With growing renewable electricity generation on the immediate horizon, there needs to be a sustainable, clean, and robust way to store this energy which is intermittent by nature. Electrochemistry and electrocatalysis allows the ability to convert abundant raw materials such as water and CO2, into highly valuable chemicals and fuels. Our groups researchers the electrocatalytic water oxidation reaction, and CO2 reduction reaction by exploring new techniques to characterize this process in-situ. See more on the electrocatalysis page.
To understand the potential scalability of solar to fuel technology, it is necessary to have realistic expectations for how much such a system would cost (in terms of money, resources and time), and how the system itself changes as it becomes bigger than what we study on the labscale. Our group has developed a rigorous technoeconomic case study for the solar production of hydrogen, while we also are constructing an up-scaled demonstration device of a modular solar to fuel system. See more on the device engineering page.