Bio-based Electrode could revolutionize Solar Energy Storage
A graphene-based electrode, which is based on the leaves of a common North American fern, has boosted solar energy storage capacity by 3,000%. Photo Credit: RMIT University
Imagine if you could power your smartphone and laptops with solar energy so their batteries would never run out of power. Ladies and gentlemen, here comes a brand-new electrode that could help you do just that by increasing solar energy storage by … wait for it … a stunning 3,000%.
A team of researchers at RMIT University in Melbourne, Australia, has created the graphene-based electrode after studying how plants succeed in storing lots of energy within tight spaces. They came across a North American plant, the western swordfern (Polystichum munitum), whose leaves pull off a feat of energy storage.
“The leaves of the western swordfern are densely crammed with veins, making them extremely efficient for storing energy and transporting water around the plant,” nanoengineer Min Gu, the head of the Laboratory of Artificial Intelligence Nanophotonics at RMIT, who was a member of the team that has published its research on improved solar energy storage. “Our electrode is based on these fractal shapes – which are self-replicating, like the mini structures within snowflakes – and we’ve used this naturally-efficient design to improve solar energy storage at a nano level.”
What the researchers did was combine this electrode with supercapacitors. “[O]ur experiments have shown our prototype can radically increase their storage capacity – 30 times more than current capacity limits,” Gu observes. “Capacity-boosted supercapacitors would offer both long-term reliability and quick-burst energy release – for when someone wants to use solar energy on a cloudy day for example – making them ideal alternatives for solar power storage.”
When the fractal-enabled laser-reduced graphene electrodes are hooked up to supercapacitors, they can hold the stored charge for much longer with minimal leakage. Better yet: because the prototype has been created with flexible thin film technology, the potential applications of the invention are endless. “The most exciting possibility is using this electrode with a solar cell to provide a total on-chip energy harvesting and storage solution,” said Litty Thekkekara, another member of the team.
“We can do that now with existing solar cells but these are bulky and rigid. The real future lies in integrating the prototype with flexible thin film solar – technology that is still in its infancy,” Thekkekara added. “Flexible thin film solar could be used almost anywhere you can imagine, from building windows to car panels, smart phones to smart watches. We would no longer need batteries to charge our phones or charging stations for our hybrid cars.”
The race can now be on to work on ever newer applications of flexible solar energy “so we can work towards achieving our vision of fully solar-reliant, self-powering electronics,” she says.