Project Title

Using fundamental chemistry to make functional materials for solar energy conversion application

Major

Chemistry

Department

Chemistry

Degree

Undergraduate

Mentor

Judith L. Jenkins

Mentor Department

Chemistry

Abstract

Population growth and rapidly increasing energy consumption necessitate innovative materials for energy conversion and storage. Viable solar fuel platforms—where the energy in sunlight is used to form storable fuels such as hydrogen gas—have not yet been realized, motivating the work presented here. In order to produce hydrogen gas from sunlight and water, a photocatalyst is required. The ideal photocatalyst for hydrogen gas generation absorbs solar photons (sunlight), producing high-energy electrons necessary for the reduction of hydrogen ions in water. The host nanocrystal studied here, zinc sulfide (ZnS), can reduce hydrogen ions to form hydrogen gas, but this material does not absorb very much sunlight. Our research focusses on increasing the amount of sunlight absorbed by the nanocrystals so that more high energy electrons are generated. We use a technique called cation exchange to substitute copper ions into the ZnS crystal; the resulting material will absorb more sunlight. Systematic control of the amount of copper incorporated into the ZnS is necessary. We hypothesize that by varying the size, shape, and flexibility of the copper source, we can sterically control the availability of copper to the ZnS nanocrystal. The experiments presented here demonstrate the synthesis and characterization of several copper sources. Preliminary cation exchange results demonstrate progress towards functional photocatalytic materials. Energy sources such as these—which have the potential to be clean, affordable, and abundant—simultaneously help solve societal energy challenges and provide opportunities for further innovation and job growth in the energy sector.

Presentation format

Poster

Poster Number

045

Share

COinS
 

Using fundamental chemistry to make functional materials for solar energy conversion application

Population growth and rapidly increasing energy consumption necessitate innovative materials for energy conversion and storage. Viable solar fuel platforms—where the energy in sunlight is used to form storable fuels such as hydrogen gas—have not yet been realized, motivating the work presented here. In order to produce hydrogen gas from sunlight and water, a photocatalyst is required. The ideal photocatalyst for hydrogen gas generation absorbs solar photons (sunlight), producing high-energy electrons necessary for the reduction of hydrogen ions in water. The host nanocrystal studied here, zinc sulfide (ZnS), can reduce hydrogen ions to form hydrogen gas, but this material does not absorb very much sunlight. Our research focusses on increasing the amount of sunlight absorbed by the nanocrystals so that more high energy electrons are generated. We use a technique called cation exchange to substitute copper ions into the ZnS crystal; the resulting material will absorb more sunlight. Systematic control of the amount of copper incorporated into the ZnS is necessary. We hypothesize that by varying the size, shape, and flexibility of the copper source, we can sterically control the availability of copper to the ZnS nanocrystal. The experiments presented here demonstrate the synthesis and characterization of several copper sources. Preliminary cation exchange results demonstrate progress towards functional photocatalytic materials. Energy sources such as these—which have the potential to be clean, affordable, and abundant—simultaneously help solve societal energy challenges and provide opportunities for further innovation and job growth in the energy sector.