Researchers have set a new efficiency record for LEDs based on perovskite semiconductors, rivaling that of the best organic LEDs (OLEDs).   Compared to OLEDs, which are widely used in high-end consumer electronics, the perovskite-based LEDs, developed by researchers at the University of Cambridge, can be made at much lower costs and can be tuned to emit light across the visible and near-infrared spectra with high color purity.  The researchers have engineered the perovskite layer in the LEDs to ...