posted on 2024-01-04, 23:03authored byWan Xue, Zongbin Zhao, Su Zhang, Yong Li, Xuzhen Wang, Jieshan Qiu
Understanding the interaction mechanisms
between the
surface of
carbon-based materials and water is of great significance for the
development of water-based energy storage and energy conversion devices.
Herein, a self-supporting electric generator is demonstrated based
on water adsorption on the surface of the carbon foam (CF) that works
with various water resources, including deionized (DI) water, tap
water, wastewater, and seawater. It is revealed that the dissociation
of oxygen-containing groups on the surface of CF after water molecule
adsorption leads to a reduction of the surface potential of the CF.
Through surface modulation techniques such as reduction and oxidation,
a balance has been uncovered between the oxygen content and conductivity
for the high-performance CFs. The generator can generate an open-circuit
voltage of approximately 0.6 V in natural seawater with a power density
of up to 0.77 mW g–1. A high voltage of more than
2 V can be achieved easily by assembling components connected in series
to drive electronic devices, such as a light-emitting diode (LED).
This work demonstrates a simple and low-cost method for electricity
harvesting, offering an additional option for self-powered devices.