The Shapes of the Future: Increasing Electrode Efficiency in Electrolysis
By Adam Patton
Senior Category (Grades 11-12)
Experiment | Energy and Natural Resources
Currently, many adverse effects of climate change are being seen around the world due to an increase in carbon dioxide and other greenhouse gases in our atmosphere. Hydrogen fuel is a promising alternative to the traditional carbon-based fuels that humans traditionally use because it can be easily made using one of the world’s most common resources, water, through the process of electrolysis.
By the year 2050, hydrogen could supply 25% of the renewable energy needed to ensure climate change will not destroy Earth (“Hydrogen, Scaling Up”, 2017). Hydrogen is a far more reliable alternative energy than traditional wind, tidal, and solar technologies because it can make energy on demand and store it for long periods of time. Along with this, a transition to hydrogen fuel is easier compared to other renewable energies because much of the current energy infrastructure that is being used can be converted to use hydrogen as a feedstock. Hydrogen fuel has the potential to be made without the release of any harmful emissions when generated using electrolysis; however, this method is costly due to the expensive platinum electrodes used in this process.
Platinum is used over other materials because of its excellent corrosion resistance and its high performance in the process of electrolysis. Currently, steam reforming of methane is used to produce hydrogen on a much larger scale than electrolysis because it uses readily available catalysts along with abundant and cost-effective carbon-based energy to power it’s reaction. When hydrogen is made using the process of steam reforming, it is no longer clean energy, taking away from the renewable potential of this fuel.
The goal of this project was to increase the efficiency of alternative metals/alloys in the process of electrolysis by altering the surface shapes of different electrodes. By doing so, alternative electrode materials could be used in hydrogen fuel production, which would lower the cost and, in turn, make it so that hydrogen fuel could be produced cleanly utilizing the process of electrolysis over using the method of steam reforming.
Part one of this project tested seven different shapes in the process of electrolysis in both the cathode and anode position against the sheet-shaped electrode used in commercial electrolysis. These shapes, all maintaining the same surface area, were hexagonal bars, square bars, round bars, dimple sheets, perforated sheets, round tubes, and square tubes. These results concluded that cathode shapes with a high amount of edge area, such as perforated sheets, dimple sheets, and hexagonal bars all increased hydrogen production the most of the shapes tested, while round tube and round bar anode shapes decreased the deterioration of the anode the most.
These results were then applied in part two of this project by coupling high performing cathode shapes with high performing anode shapes. These results found that the dimple sheet shape and the hexagonal bar shaped cathodes coupled with the round bar shaped anode both worked together to increase hydrogen production, lower deterioration, and further use of less energy than the other combinations in this project. While both shape combinations increased hydrogen production by an average of 21.4% at 12 volts and 12.4% at 32 volts compared to the control shape and lowered deterioration by 5% at 12 volts and 61% at 32 volts compared to the control, these results must be coupled with previous research to apply them into large scale processes.
Statistical analysis showed that the results gathered in this project support reliable conclusions and that the results are not dependent on the metals/alloys used, and rather the shapes themselves. This project was successful in increasing the efficiency of alternative metals/alloys in the process of electrolysis so that hydrogen can be produced in a clean, efficient, cost-effective manner, helping solve the clean energy crisis this world is experiencing.