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Title: Unbiased solar H 2 production with current density up to 23 mA cm −2 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 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.  more » « less
Award ID(s):
1834724
NSF-PAR ID:
10196370
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Energy & Environmental Science
Volume:
12
Issue:
3
ISSN:
1754-5692
Page Range / eLocation ID:
1088 to 1099
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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