MAPbBr3@PbBr(OH) Color Converter for White Light Emission and Underwater Data Transmission

Nowadays, most solid-state lighting-based visible light communication (VLC) technology suffers from the color converter’s short optical bandwidth or low stability. Herein, we fabricated MAPbBr3@PbBr(OH) nanocrystals (NCs) with high optical bandwidth and water-stable properties for color conversion of VLC and a white light-emitting diode (LED) system. The sample’s characteristic photoluminescence (PL) spectrum is green emission peaked near 529 nm. As a color converter, it has a high bandwidth capacity for devices. The sample indicates internal quantum efficiency (IQE) of about 38.33% and a PL decay time of about 5.5 ns, and it can maintain its PL properties in water for over 90 days The calculated optical bandwidth is about 49.4 MHz. Its measured −3 dB bandwidth with a 405 nm laser diode can reach 25 MHz with a data rate over 50 Mbps. More interestingly, the perovskite NCs can replace the green phosphor to build a high-speed and multicolor LED, and the −3 dB bandwidth can be maintained at over 80% in this case. These features are far beyond the abilities of commercial green phosphors. Finally, we demonstrate an underwater text transmission system with a 405 nm LED, perovskite color conversion layer, and low-cost silicon-based photodetector.