A Michigan scientist and his team have developed an inexpensive three-dimensional graphene honeycomb that they say can replace the very expensive platinum used in solar cells.Scientists focusing their efforts on lowering the cost of solar cells are seeing results using different materials.

August 23, 2013- Source: http://www.energymanagertoday.com/3d-graphene-could-replace-platinum-in-solar-cells-094810/

Image Source: http://news.rice.edu/wp-content/uploads/2014/11/1117_SOLAR-6-web.jpg