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The future of power may be on the nanoscale. Scientist around the world are currently trying to solve some of the major issues associated with todays technology. Advancements in solar cells, batteries and hydrogen fuel may one day offer us a more efficient and eco-friendly future for our power.
Nano-Sized Hydrogen Generator
A team of researchers from the U.S. Department of Energy's (DOE) Argonne National Laboratory have produced a small scale hydrogen generator that uses graphene and light to improve its production.
Hydrogen is the most abundant element in the universe, however it is rarely found in its pure form on earth.
The current commercial separation technique strips away hydrogen atoms by using natural gas to react with superheated steam. This process produces hydrogen fuel, but it also results in carbon dioxide which is classified as a greenhouse gas.
Image Credit: Rozhkova et. A transmission electron microscopic image of titanium dioxide plates resting on a near-invisible sheet of graphene.
The hydrogen generator works by using bacteriorhodopsin (bR) protein and graphene to absorb visible light. The electrons from this reaction are transported to the titanium dioxide where the materials are anchored. This process makes the titanium sensitive to visible light.
At the same time, light from the green end of the spectrum causes the bR protein to start sending protons along the membrane. The protons then make their way to the platinum nanoparticles which as placed on top of the titanium dioxide. The interaction between the protons and the electrons as they come together on the platinum results in pure hydrogen.
The majority of the research out there states that graphene principally conducts and accepts electrons. Our exploration using EPR allowed us to prove, experimentally, that graphene also injects electrons into other materials.
Argonne postdoctoral researcher Peng Wang
Improving Solar Cell Efficiency
A recent collaboration between scientists from the University of Chicago's chemistry department, the Institute for Molecular Engineering and Argonne National Laboratory has revealed a new understanding of solar power generation using polymer based devices.
The team have identified a new polymer that demonstrates improved efficiency of solar cells. The polymer boost the production of electricity by allowing an electrical charge to move more freely throughout the cell.
Polymer solar cells have great potential to provide low-cost, lightweight and flexible electronic devices to harvest solar energy.
Luyao Lu, graduate student in chemistry and lead author of a paper
Solar cells traditionally use a mixture of polymers which give and receive electrons for generating an electrical current when the cells are exposed to light. This new material developed by the team, called PID2, dramatically improves the efficiency and the level of electrical power generated when combined with a standard polymer-fullerene mixture.
Image Credit: Andrew Nelles - This solar cell consists of a new polymer, called PID2, which was developed in the laboratory of Luping Yu, professor in chemistry. The new polymer improves the efficiency of electrical power generation by 15 percent when added to a standard polymer-fullerene mixture.
Improving Battery Performance
We currently use lithium-ion batteries to power our phones, laptops, tablets and many other portable devices. Their are huge draw backs with this technology that prevent these batteries from being used in other high powered applications.
A team of researchers from Rensselaer Polytechnic Institute have now created a new material which addresses two of these limitations.
The team used nanomaterials to help alleviate the mechanical limitations typically seen in lithium-ion batteries.
To eliminate the problem of molecule decomposition, the researchers created an electrode from cobalt oxide mesoporous nanospheres. The nanospheres are shaped like small soccer balls with a series of holes sporadically scattered over the surface.
The hollow spheres experience severe mechanical and chemical degradation which results in the lose of most of their energy storage ability. However, the team noticed that after a number of discharge and charge cycles, the hollow nanospheres become refined and reactivate eventually demonstrating unprecedented performance for the battery.
Image Credit: Rensselaer Polytechnic Institute - Cobalt oxide mesoporous nanospheres
This is caused by the nanospheres pores becoming larger over time. The new structure enabled the creation of a thin but stable solid-electrolyte interface (SEI). This allowed the lithium-ions to quickly and efficiently diffuse in the electrode whilst the reactive electrode did not lose any capacity.
Nanotechnology is actively being researched and used for a variety of power generation applications with many scientists looking to solve some of the major limitations currently associated with today's technology.
Nanomaterials may offer manufacturers the ability to generate sustainable, more efficient and more powerful alternatives to current power sources, but it may be some time yet before with see these tiny production lines providing commercially accepted solutions for global power consumption.
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