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Title: Electrical decoupling of microbial electrochemical reactions enables spontaneous H 2 evolution
Hydrogen evolution is not a spontaneous reaction, so current electrochemical H 2 systems either require an external power supply or use complex photocathodes. We present in this study that by using electrical decoupling, H 2 can be produced spontaneously from wastewater. A power management system (PMS) circuit was deployed to decouple bioanode organic oxidation from abiotic cathode proton reduction in the same electrolyte. The special PMS consisted of a boost converter and an electromagnetic transformer, which harvested energy from the anode followed by voltage magnification from 0.35 V to 2.2–2.5 V, enabling in situ H 2 evolution for over 96 h without consuming any external energy. This proof-of-concept demonstrated a cathode faradaic efficiency of 91.3% and a maximum overall H 2 conversion efficiency of 28.9%. This approach allows true self-sustaining wastewater to H 2 evolution, and the system performance can be improved via the PMS and reactor optimization.  more » « less
Award ID(s):
1834724
PAR ID:
10196354
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Energy & Environmental Science
Volume:
13
Issue:
2
ISSN:
1754-5692
Page Range / eLocation ID:
495 to 502
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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