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Strongly Confined Bismuth Antimonide Quantum Dots

Khadka, Min [University of Arkansas at Little Rock, AR (United States)] (ORCID:0009000231456740)·Subedi, Rajendra [University of Arkansas at Little Rock, AR (United States)] (ORCID:0009000281733179)·Zhou, Qiaohui [Tulane University, New Orleans, LA (United States)]·Lu, Xin [Tulane University, New Orleans, LA (United States)] (ORCID:0000000299922077)·Agyei-Mensah, Joelin A. [Northern Arizona University, Flagstaff, AZ (United States)]·José-Yacamán, Miguel [Northern Arizona University, Flagstaff, AZ (United States)] (ORCID:0000000151247116)·Lang, Guillaume [Sorbonne Université, Paris (France)]·Herth, Etienne [Université de Paris-Saclay, Palaiseau (France)]·Guisbiers, Grégory [University of Arkansas at Little Rock, AR (United States)] (ORCID:0000000246156014)
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Abstract

Bismuth antimonide (Bi 1−x Sb x ) has emerged as a highly promising material for quantum applications due to its complex band structure. In this study, spherical Bi 1−x Sb x quantum dots (QDs), with a diameter of around 8 ± 2 nm, were successfully synthesized by pulsed laser ablation in liquids. The energy bandgap was determined at 2.02 ± 0.27 eV, which is significantly higher than the bulk value (∼0.025 eV). The strong confinement nature of the dots was confirmed by the Raman peak shifts. The chemical composition of the Bi 1−x Sb x QDs was measured to be around 77 ± 2 at. % of Bi and 23 ± 2 at. % of Sb. The colloid containing the Bi 1−x Sb x QDs was classified as highly stable, displaying a zeta potential of −38 ± 18 mV. Finally, the Bi 1−x Sb x QDs exhibited an electron spin resonance (ESR) signal at room temperature and at cryogenic temperature (4.2 K); consequently, revealing the presence of paramagnetic states.

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Khadka, Min [University of Arkansas at Little Rock, AR (United States)] (ORCID:0009000231456740), Subedi, Rajendra [University of Arkansas at Little Rock, AR (United States)] (ORCID:0009000281733179), Zhou, Qiaohui [Tulane University, New Orleans, LA (United States)], Lu, Xin [Tulane University, New Orleans, LA (United States)] (ORCID:0000000299922077), Agyei-Mensah, Joelin A. [Northern Arizona University, Flagstaff, AZ (United States)], José-Yacamán, Miguel [Northern Arizona University, Flagstaff, AZ (United States)] (ORCID:0000000151247116), Lang, Guillaume [Sorbonne Université, Paris (France)], Herth, Etienne [Université de Paris-Saclay, Palaiseau (France)], Guisbiers, Grégory [University of Arkansas at Little Rock, AR (United States)] (ORCID:0000000246156014). 2026-03-03. Strongly Confined Bismuth Antimonide Quantum Dots. https://doi.org/10.1021/acsmaterialsau.5c00233

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