12 July 2018
Green technique harnesses solar power to make clean fuel
Published online 16 October 2017
Scientists make an ultrathin material for storing the sun’s energy.
An international research team has synthesized a new type of ultrathin, nanoplatelet-shaped material that can help store the sun’s energy in a supercapacitor and convert it into chemical energy that splits water into oxygen and hydrogen.1
A prototype shows that the material can generate, store and deliver charge whenever needed.
This paves the way for creating multifunctional devices that operate on just sunlight, says Maher EI-Kady from Cairo University, Egypt, and one of the scientists responsible for the research.
The team, which also included researchers from Iran and the USA, prepared the material by depositing layers of common elements such as nickel, cobalt and iron on a substrate made of nickel foam.
The prototype was stable, showing only 8.7% decay in capacitance after 5,000 cycles of charging and discharging. After charging this device for 20 seconds at 1.5 volts, it successfully powered a mini-motor and drove a rotor for five minutes.
When two such devices connected in series and charged for 20 seconds at 3 volts, they were able to light up 35 green round light-emitting diodes for more than 30 minutes and run a clock for more than five hours.
According to the researchers, it’s also possible to integrate a supercapacitor and a water-splitting system; connecting a single cell to a solar cell turned on a mini-motor for a few seconds and split water.
- Shabangoli, Y. et al. An integrated electrochemical device based on earth-abundant metals for both energy storage and conversion. Energy Storage Mater. https://doi.org/10.1016/j.ensm.2017.09.010 (2017)