First-Principles Calculation of Photoelectric Property in Upconversion Materials through In³⁺ Doping.

Area of Science:

• Materials Science
• Optoelectronics
• Nanotechnology

Background:

• Multicolor upconversion luminescence (UCL) is crucial for advanced optical applications like intelligent recognition and imaging.
• Zinc oxide (ZnO) is a versatile material, but its UCL properties can be enhanced through doping.

Purpose of the Study:

• To synthesize and characterize Er³⁺, Yb³⁺, and In³⁺ codoped ZnO (Er/Yb/IZO) with a uniform block structure.
• To investigate the effect of In³⁺ doping on the multicolor UCL intensity and power sensitivity of Er/Yb/IZO.
• To explore the electronic and optical properties of Er/Yb/IZO using first-principles calculations.

Main Methods:

• Synthesis of Er/Yb/IZO with a uniform block structure.
• Experimental measurement of UCL intensity and color tuning with varying power density.
• First-principles calculations using Density Functional Theory (DFT) with a generalized gradient approximation.

Main Results:

• In³⁺ doping significantly enhances the multicolor UCL intensity of Er/Yb/IZO.
• The UCL emission of Er/Yb/I₂ZO can be tuned from red to yellow to green by increasing power density from 2.54 to 10.19 W/cm², demonstrating power sensitivity.
• DFT calculations reveal decreased band gap and enhanced optical coefficients in Er/Yb/IZO compared to pure ZnO, with increased electron density around oxygen atoms due to doping.

Conclusions:

• Er/Yb/IZO materials exhibit tunable multicolor UCL, making them suitable for power-sensitive optical applications.
• In³⁺ doping is an effective strategy to enhance UCL intensity and tune emission properties in ZnO-based materials.
• First-principles calculations provide valuable insights into the electronic structure and optical properties, guiding material design for improved performance.