The search for suitable electrodes for photoelectrochemical water splitting extends across the periodic table. While III-V semiconductors exhibit superior light gathering properties, metal oxide semiconductors generally cost less and are more robust.

The Solar Energy Activity Laboratory (SEAL) ¹ and the Heterogeneous Anodes Rapidly Perused for Oxygen Overpotential Neutralization (HARPOON)² are simple experiments that can quickly scan for suitable oxide semiconductors. The SEAL experiment measures photocurrent and the HARPOON experiment measures oxygen production efficiency. In addition, an electroplating and lithography technique³ can produce nanowires of nearly any composition that can increase the achievable current density at the electrode surface.

Electrodes made of oxides of Fe, Cr, Zn, Al, Bi, Co, and Ni were produced in our laboratory and evaluated using the SEAL and HARPOON experiments. Promising candidates were made into nanowires for additional study. This presentation will communicate the preliminary results.

REFERENCES

1. J. R. McKone et al., “The Solar Army: A Case Study in Outreach Based on Solar Photoelectrochemistry, “ Rev. Adv. Sci. Eng. 3, 288 (2014).
2. S. E. Shaner et al., “Discovering Inexpensive, Effective Catalysts for Solar Energy Conversion: An Authentic Research Laboratory Experience,” J. Chem. Educ. 93, 650 (2016).
3. http://www.unitedsci.com/product-catalog/making-wire-lithograph-pressure-sensor-nanotechnology-stem-kit