Is an effective alternative power source now possible?
A new study has produced a thin film solid oxide fuel cell that can hold an electric charge – a feat that has previously been impossible.
Researchers at the Harvard School of Engineering and Applied Knowledge have isolated a new Thin Film Solid Oxide Fuel Cell (TF-SOFC) that is capable of storing hydrogen in-situ, and therefore of generating energy for short periods of time after the fuel supply is stopped.
Solid Oxide Fuel Cells (SOFC)
Fuel cells are devices that can generate electricity from the oxidation reaction of a fuel. In Solid Oxide Fuel Cells (SOFC), the electrolyte, one of the cell components, is a solid oxide. Materials science researchers pursue these alternative fuels in hopes of producing clean and green energy, as a replacement for fossil fuels and other environmentally-unfriendly energy sources.
In standard SOFC, the electrolyte is placed between two electrodes, the anode and the cathode, where the oxidation and the reduction reactions take place, respectively. One of the fuels normally employed in SOFC is hydrogen (H2); this is oxidized into water (H2O) at the anode. At the same time the oxygen (O2) present in the air is reduced; both these reactions generate an electron flow – an electric current.
Thin Films in Hydrogen Fuel Cell Technology
In recent years, different SOFC have been developed, in which the electrolyte is a thin film, with a thickness smaller than 1 mm, deposited on an appropriate substrate. These fuel cells are appropriately called Thin Film Solid Oxide Fuel Cells (TF-SOFC). Compared to the standard SOFC, TF-SOFC are lighter, and allow lower operating temperatures with similar power density output. These fuel cells may be potential energy sources for portable electronics, once they are able to hold a charge.
Hydrogen Fuel Cells: Charge Storage
One potential limitation of SOFC is that they are unable to store energy; this means that, as soon as the H2 (or any other fuel) supply stops, the energy generation stops too. To store energy, an external storage device must be connected to the SOFC; this, however, increases both the weight and the volume of the device, thus limiting the possible applications. The ideal solution would be to develop a SOFC which can also store energy – and new research in the area has accomplished just that.
Decoding Science. One article at a time.