Storing soar energy can be more cost-effective
If platinum takes the place of molybdenum in photoelectrochemical cells, as scientist from two Swiss labs report, the technique that can increase the hydrogen production through water splitting as a way of solar energy storage.
The only form of renewable that can be explored enough to supply the everybody’s up going needs is solar energy. Still, it is highly necessary to find efficient ways of storing solar energy because there is a need for a consistent energy supply when sunlight is limited.
The most effective way to do this is to utilize solar energy to separate water into hydrogen and oxygen and get the energy back by consuming hydrogen in a fuel cell. Scientist from two labs at EPFL have found a way to create an effective method to obtain scalable solar water splitting device with cheap materials.
Sill, solar systems cannot constantly produce adequate energy since sunlight is not always the same everywhere. This can be solved with another device that is able to store energy for a later use in the form of hydrogen with very little pollution.
Through the most sustainable methods of hydrogen production is photoelectrochemical water-splitting. In this method, they use solar energy to split water molecules into hydrogen and oxygen with a process called “hydrogen evolution reaction.” This method needs a chemical agent that grows its speed, named catalyst. The most familiar catalyst in this devices is platinum, that is situated on the surface of the solar panel’s photocathode—the solar panel’s electrode that transforms light into electric current.
The team from EPFL discovered that you can make efficient solar-powered water splitting devices even with abundant and cheap materials.
The group of Xile Hu came up with a molybdenum-sulfide catalyst for the hydrogen evolution reaction, and the group of Michael Grätzel discovered that copper oxide can be a photocathode. They also found that the molybdenum sulfide can be stored on the copper(I) oxide photocathode for use in photoelectrochemical water splitting by a deposition process.
The method reveals more efficiency then other hydrogen evolution reaction catalysts like platinum. It also preserves the optical transparency for the light-harvesting surface and it offers improved stability under acidic conditions, meaning lower maintenance. Moreover, both the catalyst and the photocathode are made of cheap, earth-abundant materials that can reduce the cost of photoelectrochemical water-splitting devices. As senior author Xile Hu says, the work is a state-of-the-art example for solar hydrogen production devices.
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