Novel H2 Production System Exploiting Earth Abundant Materials and High Energy Irradiation Sources: A Study into Furthering Nuclear Power

Novel H₂ Production System Exploiting Earth Abundant Materials and High Energy Irradiation Sources: A Study into Furthering Nuclear Power

 

^{Scott Tentinger, Monica Hemmingway, Austin McKee, Wei Cheng, Syed Mubeen, University of Iowa Department of Chemical and Biochemical Engineering}

 

With the current state of the energy market and climate, it is imperative that new, sustainable forms of power generation are developed. Nuclear power plants are capable of producing power on the scale of gigawatts with comparable emissions to solar and wind power, which makes them very desirable. However, progress and expansion of the nuclear power field is heavily hindered by the public’s poor perception of its safety. This issue that can be approached with the development of novel hydrogen producing devices that utilize existing organic scintillation materials, semiconducting light absorbers, and electrocatalysts to quell public radiation concerns and create a positive value product.

To address the issue of radiation emission, the proposed work aims to develop a novel, multicomponent system for efficient conversion of high-energy radiation to a positive value chemical. This will be accomplished by co-assembling organic scintillators with semiconducting nanoparticle light absorbers and electrocatalysts. The organic scintillators are used for the conversion of high-energy, gamma radiation into lower-energy, usable Ultraviolet, UV, rays. The UV rays will then pass through to the semiconducting nanoparticles and generate electrical energy that can be used in conjunction with the electrocatalyst to induce electrolysis and produce hydrogen gas. It is hypothesized that light absorbers like Zinc Sulfide, ZnS, could be used for electrolysis of water; however, there is presently no practical way to generate a large enough flux of UV through these light absorbers to produce the energy required for electrolysis. This is where the organic scintillation aspect of the device has potential to make an impact. Using an organic scintillator like polystyrene, which has the capacity to convert gamma rays to UV, in a spent nuclear fuel pool, for example, would generate an abundance of previously unexploited UV for hydrogen production. Spent fuel pools are used to cool spent nuclear fuel rods while containing the harmful radiation the fuel rods release. Currently these pools serve simply as a means of storing materials, but if they were to be modified to produce hydrogen simultaneously, an entirely new power system could be introduced. Essentially a new fuel could be produced from previously unused decaying fuel.

Through utilization of advanced synthesis techniques, uniform coatings of organic scintillators with semiconducting nanoparticles and electrocatalyst have been achieved. Some of the techniques that have been investigated are electrophoretic deposition of polystyrene organic scintillator on FTO glass, chemical bath deposition of ZnS semiconductor on the surface of the polystyrene, and spin coating of Platinum electrocatalyst on the surface of the ZnS. The thickness of the different layers is currently being explored to maximize hydrogen evolution from the device. Platinum and ZnS are primarily being tested, but other materials are also being investigated, such as Cadmium Sulfide as an alternative for ZnS. A cheaper electrocatalyst that approaches the efficiency of platinum is also highly sought after.

Adding a hydrogen-producing element to the nuclear power process increases its marketability, as hydrogen fuel technologies are constantly evolving and moving toward wide spread use. Any new source of hydrogen would be readily accepted, especially one that would capitalize on an existing technology. Implementation of hydrogen producing devices has a great potential to reverse nuclear power’s rather poor public perception by further proving its worth as a green energy technology.