Suppressed Defect Emission and Enhanced Blue Luminescence of Zn-Doped CuBr Quantum Dots synthesized in Room-Temperature Synthesis
Year: 2026
Type: preprint
Abstract: Deep-blue-emitting CuBr quantum dots (QDs) hold promise as nontoxic and heavy-metal-free optoelectronic materials, yet their efficiency is limited by intrinsic defects. We report Zn doping as an effective strategy to mitigate defect-mediated recombination in CuBr QDs synthesized via an eco-friendly supersaturated recrystallization method under ambient conditions. XRD shows lattice contraction, Rietveld refinement confirms substitutional doping, and XPS verifies Cu$^+$/ Zn$^{2+}$ states without secondary phases. HR-TEM analysis reveals uniform 3.46 $\pm$ 0.12 nm Zn:CuBr QDs with reduced bandgap, after doping, indicating weaker quantum confinement. The dominant emission peaks appear at 406 nm ($Z_f$) and 431 nm ($Z_{1,2}$) under 365 nm excitation. Narrows defect FWHM, elevated band-edge emission, and extends carrier lifetimes, achieving 96.4 \% color purity with CIE coordinates (0.1520, 0.0395). These findings demonstrate that Zn doping is a simple, scalable, and environmentally benign strategy for engineering efficient blue-emitting CuBr QDs.
Source: arXiv (Cornell University)
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Award: G6975150144
OpenAlex ID: W7214230694