A Purdue University-led research team discovered that adding a rigid bulky molecule – bithiophenylethylammonium – to the surface of a perovskite stabilizes the movement of ions, preventing chemical bonds from breaking easily. The researchers also demonstrated that adding this molecule makes a perovskite stable enough to form clean atomic junctions with other perovskites, allowing them to stack and integrate.
“If an engineer wanted to combine the best parts about perovskite A with the best parts about perovskite B, that typically can’t happen because the perovskites would just mix together,” said Brett Savoie, a Purdue assistant professor of chemical engineering. “In this case, you really can get the best of A and B in a single material. That is completely unheard of.”
The bulky molecule is said to allow a perovskite to stay stable even when heated to 100oC. Solar cells and electronic devices require elevated temperatures of 50-80oC to operate.
These findings also mean that it could be possible to incorporate perovskites into computer chips, the researchers said in a statement. Transistors rely on junctions to control electrical current. A pattern of perovskites might allow the chip to perform more functions than with just one material.