“Coat of paint on your house may one day power it”
The Straits Times featured an interview with Prof. Castro Neto regarding the paper recently published in Science, Strong Light-Matter Interactions in Heterostructures of Atomically Thin Films.
“IT SOUNDS like science fiction, but the coat of paint on your house could one day power it entirely. In what they say is a world first, scientists from Singapore have devised new photovoltaic cells that are so ultrathin, solar panels could eventually be replaced with solar ‘paint’.
The scientists achieved this by combining graphene the world’s thinnest material and entirely made of carbon with sensitive semiconductors known as transition metal dichalcogenides or TMDCs. This makes the solar cells 150 times thinner and 15 times more sensitive than the typical ones to day which use silicon, a less sensitive semiconductor which needs to be much thicker.
In fact, the new solar cell layers are just seven atoms thick, said Professor Antonio Castro Neto, director of the Graphene Research Centre at the National University of Singapore (NUS). ‘Solar cells you see today are heavy and not flexible. These new cells are millions of times thinner than a human hair – what we’re looking at here would be the next generation of solar cells,’ he said.
Prof Castro Neto collaborated with a team of 15 scientists from across Asia and Europe for about a year. Their findings were published last Thursday in science journal Sciencexpress. Their discovery could replace current solar technologies within two decades if industry responds
favourably and manufacturing costs become competitive with other energy sources, he added.
‘You are seeing the birth of a new area of resear ch. The question is when, but yes, this is the next generation and could render silicon (cells) obsolete. Imagine, if we could cover entire surfaces of buildings with this, and harvest sunlight that way – it would be revolutionary.’
It could have huge implications for Singapore. For example, coating the entire NUS campus or HDB towns with the ‘paint’ could allow them to run completely on solar energy, he said. The same could be applied to cars or even trains, reaping huge energy savings. Singapore gets about 80 percent of its electricity from natural gas. The Government said last year that solar power could potentially meet about 15 per cent of Singapore’s electricity needs, using existing technology. The researchers’ next challenge is to synthesise the new materials on a large scale, and create prototypes they can test on actual surfaces. Said Prof Castro Neto, whose research received $10 million funding over five years from the National Research Foundation in 2011: ‘This is the first step in a long road. Since we are the world leaders on this, we can not waste this opportunity.”