A solar cell is basically a semiconductor, which converts sunlight into electricity, sandwiched between metal contacts that carry the electrical current.
But this widely used design has a flaw: The shiny metal on top of the cell actually reflects sunlight away from the semiconductor where electricity is produced, reducing the cell’s efficiency.
Now, Stanford University scientists have discovered how to hide the reflective upper contact and funnel light directly to the semiconductor below. Their findings, published in the journal ACS Nano, could lead to a new paradigm in the design and fabrication of solar cells.