Graphene finds use in next gen solar cells

Now, researchers in Berlin have found a way to exploit the wonder material in next generation solar cells, using a process which they believe could be scaled up for industrial use. The team began by examining how graphene's conductive properties change when it is incorporated into a stack of layers similar to a silicon based thin film solar cell. "We were surprised to find that these properties actually change very little," said lead researcher Marc Gluba. The next step for Gluba and his team was to grow graphene on a thin copper sheet, before transferring it to a glass substrate and coating it with a thin film of silicon. They then examined two different versions that are commonly used in conventional silicon thin film technologies: one sample contained an amorphous silicon layer, in which the silicon atoms are in a disordered state similar to a hardened molten glas; the other sample contained poly-crystalline silicon to help them observe the effects of a standard crystallisation process on graphene's properties. Even though the morphology of the top layer changed completely as a result of being heated to a temperature of several hundred degrees celcius, the graphene was still detectable. "That's something we didn't expect to find, but our results demonstrate that graphene remains graphene even if it is coated with silicon," Gluba concluded.