Efficient Orange Emission in Mn²⁺-Doped Cs₃Cd₂Cl₇ Perovskites with Excellent Stability

Area of Science:

• Materials Science
• Solid-State Chemistry
• Optoelectronics

Background:

• Low-dimensional metal halides are promising for optoelectronic devices like LEDs and solar cells.
• Poor stability hinders the commercialization of metal halide-based technologies.
• Ruddlesden-Popper (RP) phased perovskites offer a unique structural platform for material development.

Purpose of the Study:

• To synthesize a stable, high-performance perovskite material for optoelectronic applications.
• To investigate the effect of manganese (Mn²⁺) doping on the optical properties of Cs₃Cd₂Cl₇.
• To enhance the stability and photoluminescence of the material through A-site alloying.

Main Methods:

• Solvothermal synthesis method was employed to create the Ruddlesden-Popper phased perovskite Mn²⁺:Cs₃Cd₂Cl₇.
• Photoluminescence spectroscopy was used to characterize the optical properties, including quantum yield and emission spectra.
• A-site Rb alloying was explored to further improve material performance.

Main Results:

• A bright orange emission (580 nm) with a high photoluminescence quantum yield (PLQY) of ~74% was achieved upon doping Cs₃Cd₂Cl₇ with Mn²⁺.
• The Mn²⁺:Cs₃Cd₂Cl₇ exhibited excellent thermal and environmental stability.
• A-site Rb alloying further enhanced the photoluminescence intensity and stability.
• An orange LED fabricated using Mn²⁺:Cs₃Cd₂Cl₇ demonstrated outstanding color stability.

Conclusions:

• Doping with Mn²⁺ ions significantly enhances the photoluminescence properties of Cs₃Cd₂Cl₇, shifting emission to the orange spectrum.
• The synthesized Mn²⁺:Cs₃Cd₂Cl₇ offers a promising combination of high PLQY and superior stability for optoelectronic applications.
• A-site alloying provides an effective strategy to further tune and improve the performance of these perovskite materials.