Tandem photo-electrode of InGaN with two Si p-n junctions for CO2 conversion to HCOOH with the efficiency greater than biological photosynthesis

Takeyuki Sekimoto*, Shuichi Shinagawa, Yusuke Uetake, Keiichi Noda, Masahiro Deguchi, Satoshi Yotsuhashi, Kazuhiro Ohkawa

*Corresponding author for this work

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We report on a highly improved CO2 to HCOOH conversion system using a tandem photo-electrode (TPE) of InGaN and two Si p-n junctions. To improve its efficiency, narrow-band-gap InGaN was applied as the photo-absorption layer. In the TPE structure, the current matching between GaN-based photo-absorption layer and two Si p-n junctions is crucial for the improvement of the efficiency. The energy conversion efficiency for HCOOH production reached 0.97%, which is greater than average of global biological photosynthetic one.

Original languageEnglish (US)
Article number073902
JournalApplied Physics Letters
Issue number7
StatePublished - Feb 16 2015

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

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