Stanford toughens up cheap solar cells by mimicking insect eyes
The cells are made of a mineral cheaper than but as efficient as silicon.
While silicon solar panels are already providing electricity for a lot of homes and buildings, it doesn't mean researchers have stopped looking for better and cheaper alternatives. Case in point, a team of Stanford scientists working to make a cheaper photovoltaic mineral called perovskite a viable option for people who want to shift to solar. Perovskites are as efficient as silicon solar cells when it comes to converting sunlight into energy, but they're fragile and can deteriorate easily when exposed to the elements. The team had to find a way to make them more durable -- and they've found inspiration in the compound eyes of insects.
Their solution involves encapsulating perovskite microcells in a hexagon-shaped epoxy resin scaffold that measures 0.02 inches wide. They then put hundreds of those together like a honeycomb to mimic the compound eye of a fly. The study's co-lead author Nicholas Rolston says the scaffold wall protects the fragile minerals, especially since epoxy resin is "resilient to mechanical stresses."
To find out if their creation works, they tested their design by exposing it to temperatures that reached 185 degrees F and 85 percent relative humidity for six weeks. They found that the insect eye-inspired panel survived those harsh conditions while still generating electricity "at relatively high rates of efficiency." Despite their success, the researchers believe they can still boost the cells' efficiency. They're now looking for ways to be able to direct more light reflected by the scaffold into the perovskite-flled center of each cell.
