Emissive Colloidal GaAs Quantum Dots

Chang, Jun Hyuk [Univ. of Chicago, IL (United States)] (ORCID:0000000316400343); Zangeneh, Danial [Univ. of Illinois, Chicago, IL (United States)] (ORCID:0009000906505230); Chu, Heng-Chi [Univ. of Chicago, IL (United States)]; Ondry, Justin C. [Univ. of Chicago, IL (United States)] (ORCID:0000000191133420); Lin, Kailai [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000185095560); Liu, Yuan [Univ. of Chicago, IL (United States)]; Zhou, Zirui [Univ. of Chicago, IL (United States)] (ORCID:0000000167402432); Jeong, Ahhyun [Univ. of Chicago, IL (United States)] (ORCID:0000000253620700); Cassidy, James [Univ. of Chicago, IL (United States)] (ORCID:0009000967194245); Kang, Sungsu [Univ. of Chicago, IL (United States)] (ORCID:0000000182200345); Crooker, Scott A. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States). National High Magnetic Field Lab. (MagLab)] (ORCID:0000000175534718); Filatov, Alexander S. [Univ. of Chicago, IL (United States)] (ORCID:0000000283781994); Alivisatos, A. Paul [Univ. of Chicago, IL (United States)]; Rabani, Eran [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Hebrew Univ. of Jerusalem (Israel)] (ORCID:0000000320313525); Klie, Robert F. [Univ. of Illinois, Chicago, IL (United States)] (ORCID:0000000347736667); Schaller, Richard D. [Argonne National Laboratory (ANL), Argonne, IL (United States). Center for Nanoscale Materials (CNM); Northwestern Univ., Evanston, IL (United States)] (ORCID:0000000196968830); Efros, Alexander L. [Naval Research Lab. (NRL), Washington, DC (United States)] (ORCID:000000031938553X); Talapin, Dmitri V. [Univ. of Chicago, IL (United States); Argonne National Laboratory (ANL), Argonne, IL (United States). Center for Nanoscale Materials (CNM)] (ORCID:0000000264148587)

doi:10.1021/jacs.6c03474

DOE OSTI · 3377069

Emissive Colloidal GaAs Quantum Dots

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Abstract

Colloidal quantum dots offer tunable optical properties for optoelectronic applications, but the synthesis of high-quality III–V quantum dots (QDs) other than indium pnictides, and particularly GaAs, has remained elusive due to synthetic challenges. Colloidal GaAs QDs have been reported very recently and have shown only weak band-edge photoluminescence. Here, we demonstrate a large-scale synthesis of colloidal GaAs QDs in molten salts, followed by a high-temperature surface treatment with K 2 S, which removes native oxide and enables uniform zinc chalcogenide shell growth on GaAs. These QDs demonstrate bright band-edge photoluminescence and electroluminescence in QD LED devices. Low-temperature spectroscopy reveals a well-resolved exciton fine structure with distinct bright-state splitting and temperature-independent decay dynamics from 4 to 100 K. These results establish a practical pathway for the preparation of high-quality colloidal GaAs QDs from molten salts with potential applications in quantum technologies and optoelectronics.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY Exciton Fine Structure GaAs Quantum Dots Molten Salt Shell Growth

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Chang, Jun Hyuk [Univ. of Chicago, IL (United States)] (ORCID:0000000316400343), Zangeneh, Danial [Univ. of Illinois, Chicago, IL (United States)] (ORCID:0009000906505230), Chu, Heng-Chi [Univ. of Chicago, IL (United States)], Ondry, Justin C. [Univ. of Chicago, IL (United States)] (ORCID:0000000191133420), Lin, Kailai [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000185095560), Liu, Yuan [Univ. of Chicago, IL (United States)], Zhou, Zirui [Univ. of Chicago, IL (United States)] (ORCID:0000000167402432), Jeong, Ahhyun [Univ. of Chicago, IL (United States)] (ORCID:0000000253620700), Cassidy, James [Univ. of Chicago, IL (United States)] (ORCID:0009000967194245), Kang, Sungsu [Univ. of Chicago, IL (United States)] (ORCID:0000000182200345), Crooker, Scott A. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States). National High Magnetic Field Lab. (MagLab)] (ORCID:0000000175534718), Filatov, Alexander S. [Univ. of Chicago, IL (United States)] (ORCID:0000000283781994), Alivisatos, A. Paul [Univ. of Chicago, IL (United States)], Rabani, Eran [University of California, Berkeley, CA (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Hebrew Univ. of Jerusalem (Israel)] (ORCID:0000000320313525), Klie, Robert F. [Univ. of Illinois, Chicago, IL (United States)] (ORCID:0000000347736667), Schaller, Richard D. [Argonne National Laboratory (ANL), Argonne, IL (United States). Center for Nanoscale Materials (CNM); Northwestern Univ., Evanston, IL (United States)] (ORCID:0000000196968830), Efros, Alexander L. [Naval Research Lab. (NRL), Washington, DC (United States)] (ORCID:000000031938553X), Talapin, Dmitri V. [Univ. of Chicago, IL (United States); Argonne National Laboratory (ANL), Argonne, IL (United States). Center for Nanoscale Materials (CNM)] (ORCID:0000000264148587). 2026-05-29. Emissive Colloidal GaAs Quantum Dots. https://doi.org/10.1021/jacs.6c03474

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