Warwick team hails lead-free perovskite solar breakthrough

Perovskite solar cells – one of the most promising emerging solar energy materials – have moved a step closer to mass commercialisation thanks to the discovery that they can be made with tin.

Perovskites are the most rapidly advancing solar technology and in recent years their efficiency has improved dramatically.

Relatively cheap to produce they are lightweight and compatible with flexible substrates, so could be applied more widely than the rigid flat plate silicon solar cells that currently dominate the photovoltaics market, particularly in consumer electronics and transportation applications

However, until now, their reliance on lead – which is toxic – has been something of a barrier to commercialisations.

In a paper published in Nature Energy, a group from the University of Warwick has demonstrated that perovskites using tin in place of lead are more stable than previously thought, and so could prove to be a viable alternative to lead perovskites for solar cells.

The team has also shown how the device structure can be simplified without compromising performance, which offers the important advantage of reduced fabrication cost.

The group claims that lead-free cells could render solar power cheaper, safer and more commercially attractive: leading to it becoming a more prevalent source of energy in everyday life.

Commenting on the work, lead researcher Dr Ross Hatton said: “It is hoped that this work will help to stimulate an intensive international research effort into lead-free perovskite solar cells, like that which has resulted in the astonishingly rapid advancement of lead perovskite solar cells.”