A molecular tandem cell for efficient solar water splitting
Degao Wang, Jun Hu, Benjamin D. Sherman, Matthew V. Sheridan, Liang Yan, Christopher J. Dares, Yong Zhu, Fei Li, Qing Huang, Wei You, Thomas J. Meyer
Abstract
Significance A major challenge for artificial photosynthesis is creating a photoelectrode to split water without an added bias. Here, we demonstrate the value of combining of a dye-sensitized photoelectrosynthesis cell and an organic solar cell in a photoanode for water oxidation. With the two component electrodes, and a counter Pt electrode for H 2 evolution, the electrode becomes part of a combined electrochemical cell for unassisted water splitting, 2H 2 O → O 2 + 2H 2 . The results described here offer a major improvement in solar-to-hydrogen conversion efficiency (STH%) for a molecularly based solar fuel electrode. The STH% for water splitting was 1.5% for the tandem cell compared to ∼1% for natural photosynthesis.