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We created innovative supercapacitive micro-bio-photovoltaic systems (or micro-BPVs) with maximized bacterial photoelectrochemical activities in a wellcontrolled, tightly enclosed micro-chamber. The technique was based on a 3-D doublefunctional bio-anode concurrently exhibiting bio-electrocatalytic and charge-storage features so that it offers the high-energy harvesting function of BPVs and the highpower operation of an internal supercapacitor for charging and discharging. During the charging-discharging operation with 3 min of charging and 2 min of discharging, our device produced a maximum power density of 19.12 μW/cm2 and current density 212.09 μA/cm2, a performance significantly greater than that of the continuous discharging mode. This work creates a microscale hybrid energy-harvesting device that combines a biological photovoltaic device and a supercapacitor for self-sustainable field applications.
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Generic Air‐Gen Effect in Nanoporous Materials for Sustainable Energy Harvesting from Air Humidity
Abstract Air humidity is a vast, sustainable reservoir of energy that, unlike solar and wind, is continuously available. However, previously described technologies for harvesting energy from air humidity are either not continuous or require unique material synthesis or processing, which has stymied scalability and broad deployment. Here, a generic effect for continuous energy harvesting from air humidity is reported, which can be applied to a broad range of inorganic, organic, and biological materials. The common feature of these materials is that they are engineered with appropriate nanopores to allow air water to pass through and undergo dynamic adsorption–desorption exchange at the porous interface, resulting in surface charging. The top exposed interface experiences this dynamic interaction more than the bottom sealed interface in a thin‐film device structure, yielding a spontaneous and sustained charging gradient for continuous electric output. Analyses of material properties and electric outputs lead to a “leaky capacitor” model that can describe how electricity is harvested and predict current behaviors consistent with experiments. Predictions from the model guide the fabrication of devices made from heterogeneous junctions of different materials to further expand the device category. The work opens a wide door for the broad exploration of sustainable electricity from air.
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- PAR ID:
- 10415633
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 36
- Issue:
- 12
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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