Photoelectrochemical cell and energy system using same

摘要

A photoelectrochemical cell (100) includes: a semiconductor electrode (120) including a conductor (121), a first n-type semiconductor layer (122) having a nanotube array structure, and a second n-type semiconductor layer (123); a counter electrode (130) connected to the conductor (121); an electrolyte (140) in contact with the second n-type semiconductor layer (123) and the counter electrode (130); and a container (110) accommodating the semiconductor electrode (120), the counter electrode (130) and the electrolyte (140). Relative to a vacuum level, (I) band edge levels of a conduction band and a valence band in the second n-type semiconductor layer (123), respectively, are higher than band edge levels of a conduction band and a valence band in the first n-type semiconductor layer (122), (II) a Fermi level of the first n-type semiconductor layer (122) is higher than a Fermi level of the second n-type semiconductor layer (123), and (III) a Fermi level of the conductor (121) is higher than the Fermi level of the first n-type semiconductor layer (122).

主权项

1. A photoelectrochemical cell comprising:
a semiconductor electrode including a conductor, a first n-type semiconductor layer that is disposed on the conductor and has a nanotube array structure, and a second n-type semiconductor layer disposed on the first n-type semiconductor layer; a counter electrode connected electrically to the conductor; an electrolyte in contact with surfaces of the second n-type semiconductor layer and the counter electrode; and a container accommodating the semiconductor electrode, the counter electrode and the electrolyte, wherein: in the semiconductor electrode, relative to a vacuum level, (I) band edge levels of a conduction band and a valence band in the second n-type semiconductor layer, respectively, are higher than band edge levels of a conduction band and a valence band in the first n-type semiconductor layer, (II) a Fermi level of the first n-type semiconductor layer is higher than a Fermi level of the second n-type semiconductor layer, and (III) a Fermi level of the conductor is higher than the Fermi level of the first n-type semiconductor layer; and the photoelectrochemical cell generates hydrogen by irradiation of the second n-type semiconductor layer with light.