Unbiased photoelectrochemical hydrogen production with high efficiency and durability is highly desired for solar energy storage. Here, we report a microbial photoelectrochemical (MPEC) system that demonstrated superior performance when equipped with bioanodes and black silicon photocathode with a unique “Swiss-cheese” interface. The MPEC utilizes the chemical energy embedded in wastewater organics to boost solar H 2 production, which overcomes barriers on anode H 2 O oxidation. Without any bias, the MPEC generates a record photocurrent (up to 23 mA cm −2 ) and retains prolonged stability for over 90 hours with high Faradaic efficiency (96–99%). The calculated turnover number for MoS x catalyst during a 90 h period is 495 471 with an average frequency of 1.53 s −1 . The system replaced pure water on the anode with actual wastewater and achieved waste organic removal up to 16 kg COD m −2 photocathode per day. Cost credits from concurrent wastewater treatment and low-cost design make photoelectrochemical H 2 production practical for the first time.
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Unbiased solar H2 production with current density up to 23 mA cm2 by Swiss-cheese black Si coupled with wastewater bioanode
Unbiased photoelectrochemical hydrogen production with high efficiency and durability is highly desired for solar energy storage. Here, we report a microbial photoelectrochemical (MPEC) system that demonstrated superior performance when equipped with bioanodes and black silicon photocathode with a unique ‘‘Swiss-cheese’’ interface. The MPEC utilizes the chemical energy embedded in wastewater organics to boost solar H2 production, which overcomes barriers on anode H2O oxidation. Without any bias, the
MPEC generates a record photocurrent (up to 23 mA cm2) and retains prolonged stability for over 90 hours with high Faradaic efficiency (96–99%). The calculated turnover number for MoSx catalyst during a 90 h period is 495 471 with an average frequency of 1.53 s1
. The system replaced pure water on the anode with actual wastewater and achieved waste organic removal up to 16 kg COD m2 photocathode per day. Cost credits from concurrent wastewater treatment and low-cost design make photoelectrochemical H2 production practical for the first time
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- Award ID(s):
- 1704992
- NSF-PAR ID:
- 10093790
- Date Published:
- Journal Name:
- Energy & environmental science
- Issue:
- 12
- ISSN:
- 1754-5706
- Page Range / eLocation ID:
- 1088-1099
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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