From allowing man to make fire to being used as paper, trees have enabled us humans to advance dramatically – but now they can be used to create high-tech storage devices.
The discovery by chemists at Oregon State University, US, means that trees can be used to help power new cars, electronics and even in the aviation industry.
Scientists – who were barking up the right tree – found that cellulose, a key component of plant cells, can be heated in the presence of ammonia and turned into a key component for supercapacitors.
The exposure to high heat and ammonia converts the cellulose from the trees to a carbon material, which is needed for supercapacitors.
Supercapacitors, which can hold more power than a battery, can be used in computers and consumer electronic,s as well as heavy industries to power items as large as cranes.
A supercapacitor can capture energy that might otherwise be wasted, such as in braking operations. Their energy storage abilities may help ‘smooth out’ the power flow from alternative energy systems, such as wind energy.
They can power a defibrillator, open the emergency slides on an aircraft and greatly improve the efficiency of hybrid electric automobiles.
They can also be charged quickly, but will equally lose that charge quicker than batteries.
David Xiulei Ji, from the university, said: “There are many applications of supercapacitors around the world, but right now the field is constrained by cost.”
“If we use this very fast, simple process to make these devices much less expensive, there could be huge benefits.”
He continued: “It’s surprising that such a basic reaction was not reported before. Not only are there industrial applications, but this opens a whole new scientific area, studying reducing gas agents for carbon activation.
“We’re going to take cheap wood and turn it into a valuable high-tech product.”
The findings will also lead to the ability to produce supercapacitors at a much cheaper cost than has been previously possible, the university says.
As well as being cheaper the production of the electrodes of a supercapacitor will also be able to be done in an environmentally friendly way.
Ji, an assistant professor of chemistry at the university, said: “The ease, speed and potential of this process is really exciting.
“For the first time we’ve proven that you can react cellulose with ammonia and create these N-doped nanoporous carbon membranes.”
The membranes at the nano-scale are incredibly thin. A single gram of them can have a surfaces area of nearly 2,000 square metres. This is what allows them to be useful in supercapacitors.
Final image courtesy of David Xiulei Ji / Oregon State University