Decreasing Structural Dimensionality of Double Perovskites for Phase Stabilization toward Efficient X-ray Detection

Area of Science:

• Materials Science
• Solid-State Chemistry
• Optoelectronics

Background:

• Halide double perovskites are promising for optoelectronics due to low toxicity and high stability.
• Their properties, like band gap and carrier transport, are often fixed due to halide type constraints.
• A strategy to overcome these limitations is needed to expand their applicability.

Purpose of the Study:

• To synthesize novel two-dimensional (2D) silver-indium-bromide double perovskites.
• To investigate their semiconducting, photoluminescence, and X-ray detection properties.
• To explore a new pathway for developing stable, low-toxicity perovskites with tunable optoelectronic performance.

Main Methods:

• Synthesis of (PEA)4AgInBr8 and (i-BA)4AgInBr8 using long-chain organic amines to replace chloride with bromide.
• Density functional theory (DFT) calculations for theoretical insights.
• Spectroscopy and electrical characterization for property evaluation.

Main Results:

• Successful synthesis of two novel 2D silver-indium-bromide double perovskites.
• Demonstrated semiconducting behavior with excellent carrier transport (μτ product: 2.0 × 10⁻³ cm² V⁻¹).
• Achieved high X-ray detection sensitivity (185 μC Gyair⁻¹ cm⁻²) due to heavy atoms and stable baseline.

Conclusions:

• The introduction of long-chain organic amines enables complete bromide substitution in double perovskites.
• These novel bromide double perovskites exhibit superior optoelectronic and X-ray detection properties.
• This work expands the family of double perovskites, offering a new route for stable, low-toxicity materials with retained performance.