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DOE OSTI · 2203703

Stable Cadmium-Free Quantum Dot Optical Down-Converters for Solid State Lighting

Jen-La Plante, Ilan·Kelley, David F
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Abstract

Quantum dots (QDs) have been used in commercial solid-state lighting (SSL) applications to improve the energy efficiency of light generation at warm color temperatures. By increasing the amount of QDs used in each product, further energy savings are possible; however, traditional QDs contain cadmium, which has regulatory limits on its concentration in consumer products. As described within this final technical report, we have established that heavy-metal free QDs made from indium phosphide (InP) exhibit highly efficient emission at the temperatures and fluxes relevant to SSL. However, the maintenance of this emission is compromised during long term operation due to QD oxidation. We have identified multiple methods to slow the oxidation rate, which has improved the operational stability of these materials more than 200 times longer than at the project start. Beyond these improvements, heavy-metal free QDs require a further hundred-fold increase in stability to enable use in mid-power SSL and a ten-fold increase in stability to enable use in diffuse SSL applications. The outcomes of this project demonstrate feasibility for the use of heavy-metal free QDs in commercial SSL applications with potential use in diffuse SSL applications in the near term (1-2 years) pending market need.

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32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION36 MATERIALS SCIENCEdownconverterfluxquantum dotssolid-state lightingstability

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Jen-La Plante, Ilan, Kelley, David F. 2023-10-27. Stable Cadmium-Free Quantum Dot Optical Down-Converters for Solid State Lighting. https://doi.org/10.2172/2203703

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