University of California

Ming Lee Tang

Xin Li

Zhiyuan Huang

Christopher John Bardeen

Kerry Miller Hanson

Melika Mahboub

The ability to upconvert two low energy photons into one high energy photon has potential applications in solar cells, photodetectors and data storage. In this disclosure, CdSe and PbSe semiconductor nanocrystals are combined with molecular emitters (diphenylanthracene and rubrene) to upconvert photons in both the visible and near infrared spectral regions. Absorption of low energy photons by the nanocrystals is followed by energy transfer to the molecular triplet states, which then undergo triplet-triplet annihilation to create high energy singlet states that emit upconverted light. By using conjugated organic ligands on the nanocrystals to form an energy cascade, the upconversion process can be enhanced by up to three orders of magnitude. The use of different combinations of nanocrystals and emitters shows that this platform has great flexibility in the choice of both excitation and emission wavelengths.

Hybrid molecule-nanocrystal photon upconversion across the visible and near-infrared

Provided herein are transmitter ligands that improve photon upconversion of near infrared light (NIR) to visible light. The presently provided ligands are complexed to semiconductor nanocrystals and improve triplet energy transfer from semiconductor nanocrystal to annihilator in triplet-triplet annihilation. Suitable applications include bio-imaging.

Growing community of inventors

Riverside, CA, United States of America

Ming Lee Tang