Scientists have proved what Popeye always knew: spinach is an excellent energy source. It’s so good that in 10 years, mobile phones and portable computers may be coated in a spinach-based material that provides their electrical power.
Scientists have proved what Popeye always knew: spinach is an excellent energy source.
It’s so good that in 10 years, mobile phones and portable computers may be coated in a spinach-based material that provides their electrical power.
“The phone is no longer red or blue; it becomes green,” said Shuguang Zhang, associate director of the Centre for Biomedical Engineering at the Massachusetts Institute of Technology.
In exchange for the colour makeover, users would have electrical devices that could recharge themselves from sunlight, using a process similar to the photosynthesis that keeps all green plants alive.
Dr Zhang and his MIT colleagues developed the technology with scientists at the University of Tennessee and the US Naval Research Laboratory. They isolated a set of spinach proteins that produce energy when exposed to light. The proteins form clusters no more than 20 nanometers in size, meaning that 100,000 would fit on the head of a pin.
Next, they had to solve how to bond this material with electrical circuitry. Dr Zhang figured out how to use broken pieces of proteins, called peptides, to attach the spinach protein to a piece of glass coated with a thin layer of gold. When hit with light from a laser, the resulting chip produced a tiny stream of electrical current.
Dr Zhang said billions of years of evolution had taught plants to use sunlight efficiently, so a bio-solar device should be capable of higher efficiency than present-day systems. Also, the bio-engineered materials were so thin that thousands of layers of them could be compressed into the width of a human hair. “It’s like a layer of paint,” he said.
How long before our mobile phones turn green?
It’s just a matter of money to transform the lab experiment into practical products, Dr Zhang says. Chip maker Intel has agreed to provide research funds.
Author: Hiawatha Bray
News Service: Boston Globe