The effects of exchange current density, Tafel slope, system resistance, electrode area, light intensity, and solar cell efficiency were systematically decoupled at the converter-assisted photovoltaic-water electrolysis system. This allows key determinants of overall efficiency to be identified. On the basis of this model, 26.5% single-junction GaAs solar cell was combined with a membrane-electrode-assembled electrolysis cell (EC) using the dc/dc converting technology. As a result, we have achieved a solar-to-hydrogen conversion efficiency of 20.6% on a prototype scale and demonstrated light intensity tracking optimization to maintain high efficiency. We believe that this study will provide design principles for combining solar cells, ECs, and new catalysts and can be generalized to other solar conversion chemical devices while minimizing their power loss during the conversion of electrical energy into fuel.
Bibliographical noteFunding Information:
This research was supported by the Global Frontier R&D Program of the Center for Multiscale Energy System funded by the National Research Foundation under the Ministry of Science, ICT and Future, Korea (2012M3A6A7054855), and by the Ministry of Trade, Industry and Energy (MOTIE) under Industrial Strategic Technology Development Program, Korea (0417-2016-0019).
© 2017 American Chemical Society.
ASJC Scopus subject areas
- General Chemistry
- General Chemical Engineering