10.57647/jnsc.2025.1506.25

Anion-Engineered Cobalt Salts as Exogenous Modulators for Phase Tailoring in CsPbBr3 Nanocrystals: Minimal Doping Towards Enhanced Color Fidelity, and stable White LEDs

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Supplementary Information
  • Hairong Zhao1,
  • Anxin Shuai2,
  • Ran Huang2,
  • Kaliyamoorthy Justice Babu3,
  • Muhammad Moin1,
  • Chengjie Wang1,
  • Mehrunisa Moin1,
  • Sonu Kumar1,
  • Indra Neel Pulidindi4,
  • Arup Neogi1,
  • Yixi Wang2,
  • Marek Piotrowski1,
  • Udayabhaskararao Thumu1,
  1. Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, China
  2. School of New Energy Materials and Chemistry, Leshan Normal University, Leshan, Sichuan 614000, China
  3. Institute of Nano Science and Technology, Mohali, Punjab 140306, India
  4. Saveetha Institute of Medical and Technical Sciences (SIMATS), Thandalam, Chennai, 602105, India

Published in Issue 28-12-2025

Copyright (c) 2025 Hairong Zhao, Anxin Shuai, Ran Huang, Kaliyamoorthy Justice Babu, Muhammad Moin, Chengjie Wang, Mehrunisa Moin, Sonu Kumar, Indra Neel Pulidindi, Arup Neogi, Yixi Wang, Marek Piotrowski, Udayabhaskararao Thumu (Author)

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This work is licensed under a Creative Commons Attribution 4.0 International License.

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Zhao, H., Shuai, A., Huang, R., Babu, K. J., Moin, M., Wang, C., Moin, M., Kumar, S., Pulidindi, I. N., Neogi, A., Wang, Y., Piotrowski, M., & Thumu, U. (2025). Anion-Engineered Cobalt Salts as Exogenous Modulators for Phase Tailoring in CsPbBr3 Nanocrystals: Minimal Doping Towards Enhanced Color Fidelity, and stable White LEDs . Journal of Nanostructure in Chemistry, 15(06). https://doi.org/10.57647/jnsc.2025.1506.25
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Abstract

Doping colloidal CsPbBr3 perovskite nanocrystals (NCs) provides an effective strategy to enhance their optoelectronic properties and expand their application potential in display technologies, enabling high color fidelity (Rf) in white-LEDs (WLEDs). Although an excess of Pb²⁺ is known to promote phase-pure and emissive CsPbBr3 NCs, the influence of exogenous dopant precursor chemistry—particularly the counter-anion and the metal ion-to-lead ratio remains poorly understood. In this work, we systematically investigate cobalt precursor identity and Pb: Co feed ratios in Co:CsPbBr3 NCs synthesized by hot injection. Three cobalt salts—CoBr2 (bCo), Co(CH₃COO)₂ (aCo), and Co(NO₃)₂ (nCo), were investigated (0.16–3.35 at% doping). Among the bCo produced the best results, retaining the perovskite phase and high photoluminescence (~60%) at low loading, while aCo and nCo induced non-emissive Cs4PbBr6 formation, and high bCo loading led to nanosheet morphologies. In WLEDs, bCo:CsPbBr3 (8:2) demonstrated high color accuracy, superior stability compared to pristine and other doped NCs. Importantly, bCo:CsPbBr3 retained ~92% of its initial color fidelity over 10 minutes, whereas pristine CsPbBr3 retained only ~78%. Moreover, the WLEDs exhibited a wide color gamut (~122.9% NTSC, ~91.7% Rec. 2020), highlighting the crucial role of dopant precursor selection in optimizing phase stability, doping efficiency, and device performance.

Keywords

  • Cesium lead bromide,
  • Cobalt precursors,
  • Doping,
  • Anion effect,
  • White light-emitting diodes (WLEDs)
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References

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