Preparation of CsPb(Cl/Br)

Area of Science:

• Materials Science
• Nanotechnology
• Solid-State Chemistry

Background:

• Cesium lead halide perovskite (CsPbX3) nanocrystals (NCs) exhibit a single emission peak and undergo rapid anion exchange, limiting their use in white light-emitting diodes (WLEDs).
• Composite structures can enhance perovskite stability and passivate surface defects, but complex post-treatments often cause NC dissolution.

Purpose of the Study:

• To develop a stable CsPb(Cl/Br)3/TiO2:Eu3+ composite for direct white light excitation without additional treatment.
• To improve the stability and performance of perovskite-based WLEDs.

Main Methods:

• In-situ growth of CsPb(Cl/Br)3 NCs within Eu3+-doped TiO2 hollow shells using a modified thermal injection method.
• Utilizing TiO2 shells as a substrate for Eu3+ doping and as a protective layer against PL quenching molecules.

Main Results:

• The CsPb(Cl/Br)3/TiO2:Eu3+ composite exhibited direct white light emission.
• WLEDs fabricated with these composites showed bright white light, a luminous efficiency of 87.39 lm/W, and enhanced long-time operating stability.
• The TiO2 hollow shells effectively protected the CsPb(Cl/Br)3 NCs, preventing degradation and maintaining crystal structure.

Conclusions:

• The in-situ growth of CsPb(Cl/Br)3 NCs in Eu3+-doped TiO2 hollow shells provides a promising strategy for developing stable and efficient perovskite-based WLEDs.
• This approach overcomes limitations of single-component perovskite NCs and complex post-treatment methods.
• The composite material offers a new avenue for advancing perovskite optoelectronic devices.