Visible-Light Photodetection by Zero-Dimensional Hybrid Indium-Halide with Minimal Structural Distortion and Reduced...

Area of Science:

• Materials Science
• Solid-State Physics
• Photodetector Technology

Background:

• Zero-dimensional (0D) hybrid halides offer excellent light emission but lack charge separation for photovoltaics.
• Existing 0D materials suffer from radiative recombination due to isolated inorganic polyhedra.

Purpose of the Study:

• To enhance visible-light photodetection capabilities in 0D hybrid halides.
• To overcome limitations of charge separation and radiative recombination in 0D materials.

Main Methods:

• Designed a new 0D hybrid halide, C24H72N8In2Br14 (HIB), using 1,6-hexanediammonium (HDA) cation.
• Incorporated closely-spaced dissimilar [InBr6]3- octahedra and [InBr4]- tetrahedra units linked by HDA.
• Introduced bromine vacancies in the [InBr4]- block to tune the band gap.

Main Results:

• HIB exhibits enhanced carrier density, mobility, and diffusion coefficient compared to CIB.
• The material has a reduced direct band gap of 2.19 eV due to mid-gap states from bromine vacancies.
• Achieved high responsivity (9975.9±201.6 mA/W at 3V) and excellent self-powered photodetection (81.2±3.0 mA/W, 6.98×10^9 Jones).

Conclusions:

• Close spacing of dissimilar polyhedra and HDA linkers significantly improve photodetection performance.
• HIB demonstrates superior performance among low-dimensional hybrid halides for visible-light detection.
• The developed material shows promise for high-performance, self-powered photodetector applications.