A team of researchers at the University of Notre Dame has made a major advance toward this vision by creating an inexpensive “solar paint” that uses semiconducting nanoparticles to produce energy.
The team’s search for the new material, described in the journalACS Nano, centered on nano-sized particles of titanium dioxide, which were coated with either cadmium sulfide or cadmium selenide. The particles were then suspended in a water-alcohol mixture to create a paste.
When the paste was brushed onto a transparent conducting material and exposed to light, it created electricity.
"The best light-to-energy conversion efficiency we’ve reached so far is 1 percent, which is well behind the usual 10 to 15 percent efficiency of commercial silicon solar cells," explains Kamat.
"But this paint can be made cheaply and in large quantities. If we can improve the efficiency somewhat, we may be able to make a real difference in meeting energy needs in the future."
^This sounds like an amazing breakthrough, however, it contains cadmium (which is a highly toxic heavy metal) and alcohol is used during production. Have to consider the cost-benefits of using a product which could cause precipitous damage to both human health and the environment.