Layered Perovskite Doping with Eu³⁺ and β-diketonate Eu³⁺ Complex

Area of Science:

• Materials Science
• Optoelectronics
• Inorganic Chemistry

Background:

• Metal halide perovskites are key for light-emitting devices.
• Doping enhances perovskite functionality, luminescence yield, and tunability.
• Lanthanide doping, particularly with europium (Eu3+), offers intense, line-like luminescence but remains less explored than other dopants.

Purpose of the Study:

• To investigate the doping of NMA2PbBr4 layered perovskites with Eu3+ and a Eu3+ tetrakis β-diketonate complex.
• To evaluate the impact of the naphthalene-based cation (NMA) on direct Eu3+ sensitization.
• To assess the effectiveness of protecting Eu3+ within a β-diketonate complex for improved energy transfer and luminescence.

Main Methods:

• Synthesis of NMA2PbBr4 layered perovskites doped with Eu3+ and Eu3+ tetrakis β-diketonate complex.
• Utilizing the antenna effect of the 1-naphtylmethylammonium (NMA) cation for energy transfer.
• Characterization of luminescence properties and comparison between direct doping and complex doping.

Main Results:

• Direct sensitization of Eu3+ in NMA2PbBr4 perovskites was achieved via the NMA cation's antenna effect.
• Direct doping showed limited efficiency due to suboptimal energy level alignment between NMA and Eu3+.
• Eu3+ protected within a tetrakis β-diketonate complex exhibited a nearly 30-fold increase in luminescence yield.
• The complex provided a more favorable coordination environment and energy landscape for efficient energy transfer.

Conclusions:

• Europium tetrakis β-diketonate complex doping offers a superior strategy for enhancing luminescence in layered perovskites compared to direct Eu3+ doping.
• The protective complex facilitates efficient energy transfer, overcoming limitations of direct sensitization.
• This approach paves the way for designing advanced perovskite/lanthanide host-guest systems with tailored and improved optoelectronic properties.