Improved Visible Emission from ZnO Nanoparticles Synthesized via the Co-Precipitation Method

Area of Science:

• Materials Science
• Nanotechnology
• Solid State Physics

Background:

• Zinc oxide nanoparticles (ZnO NPs) exhibit intrinsic defects enabling visible light emission without doping.
• These properties make ZnO NPs promising for light sources and energy downshifting applications.
• Achieving high photoluminescence quantum efficiency (PL QY) from defect emission in ZnO NPs remains a challenge.

Purpose of the Study:

• To identify co-precipitation synthesis parameters for achieving high visible PL QY in ZnO NPs.
• To investigate the influence of precursors and alkaline hydroxides on ZnO NP emission properties.
• To enhance visible emission efficiency through controlled synthesis and understanding of defect contributions.

Main Methods:

• Co-precipitation synthesis of ZnO nanoparticles.
• Varied zinc precursors and alkaline hydroxides (KOH, LiOH).
• Analysis of nanoparticle size, morphology, surface stabilization, and spectral contributions.

Main Results:

• The choice of zinc precursor and alkaline hydroxide significantly impacts emission spectra and PL QY.
• Lithium hydroxide (LiOH) addition during synthesis markedly enhances visible emission efficiency.
• Visible emission efficiency was increased up to 13% by incorporating LiOH.

Conclusions:

• Optimized co-precipitation parameters, particularly the use of LiOH, are crucial for high-efficiency visible emission from ZnO NPs.
• Controlling nanoparticle characteristics and understanding spectral contributions can further improve defect-related luminescence.
• This work provides a pathway for developing efficient ZnO NP-based light-emitting materials.