This innovation converts insulating nanoparticles into LEDs emitting high-purity near-infrared light, supporting applications in optical communication, deep-tissue imaging and biomedical sensing.
As biomedical sensing, optical communications and high-precision devices demand ultra-pure near-infrared light, conventional materials face limitations. Many nanoparticles that emit exceptionally pure light are electrically insulating, preventing their integration into LEDs and other electronic systems.
Researchers at the Cavendish Laboratory, University of Cambridge, have developed a method to electrically power these nanoparticles using organic molecules that act as molecular antennas. This innovation allows the first light-emitting diodes based on lanthanide-doped nanoparticles to operate under normal conditions.
The nanoparticles emit highly stable light in the second near-infrared window, ideal for deep-tissue imaging, but their insulating nature has been a barrier. The team created an organic-inorganic hybrid by anchoring 9-anthracenecarboxylic acid molecules to the nanoparticle surface. Electrical charges are injected into the molecules, which transfer energy through a triplet state to the nanoparticles with over 98% efficiency, producing electroluminescence.
Key features of the research include:
- Electrical powering of insulating lanthanide nanoparticles
- Narrow spectral width for high-purity near-infrared emission
- Low operating voltage around 5 volts
- Higher spectral purity than quantum dot LEDs
- Peak external quantum efficiency exceeding 0.6 percent
Dr Yunzhou Deng, a lead author of the study and postdoctoral research associate at the university says, “This is just the beginning, we can now explore many combinations of organic molecules and insulating nanomaterials to create devices with tailored properties.” as this method can open doors to next-generation medical imaging, optical communication and biological sensing.
