Researchers at  the University of New South Wales have found a way to make very high efficiency solar cells out of cheap, low-grade silicon.

It has been known for several decades that hydrogen atoms can be introduced into the atomic structure of silicon to help correct defects. But researchers have had limited success in controlling the hydrogen to maximise its benefits or even understanding why this happens.

According to Professor Stuart Wenham from the School of Photovoltaics and Renewable Energy Engineering at UNSW “Our research team at UNSW has worked out how to control the charge state of hydrogen atoms in silicon – something that other people haven’t previously been able to do.”

The charge state determines how well the hydrogen can move around the silicon and its reactivity, which is important to help correct the defects.

Professor Wenhan says that “We have seen a 10,000 times improvement in the mobility of the hydrogen and we can control the hydrogen so it chemically bonds to things like defects and contaminants, making these inactive”.

The UNSW team is working with industry partners and equipment manufacturers to bring ithe technology market.