Student Poster Presentation #9 (Session 1)
New Type of Bulk-Quantum Materials Based on Zero-Dimensional
Crystal Structures
Haoran Lin, Prof. Biwu Ma
Chemical and Biomedical Engineering, FSU
Abstract
A traditional ionic crystal constitutes charged atoms or molecules that are aligned periodically in the crystal’s
lattice. Usually, a three-dimensional (3-D) ionic crystal exhibits strong coulombic interactions between ions in all
directions which means that the constituents are intensely coupled and form band structures in its energy diagram.
Figure 1. Single-crystal structure of (DMEDABr) 4 SnBr 6 0-D material.
A recently study in our group reveals that, a zero-dimensional ionic crystal can be achieved by combining a metal-
halide ion and a large organic ligand ion (Figure 1). In this structure, the SnBr 64- ions are surrounded by the bulky
ligands which ensures a large distance between the metal-halide anions. Since the metal-halide cores are isolated
from each other, no band structure is formed and the single crystal exhibits strong quantum-confinement effect as
the inherent property of the metal-halide constituent. Also, due to elimination of the non-emissive recombination
channels, the 0-D crystal can achieve a photoluminescence quantum efficiency near 100%. This discovery
suggests strong potential application in LEDs, lighting, solar concentrators etc. and opens a research area that is
barely explored before.
According to our previous results, my research focuses on developing new organic-inorganic hybrid compounds
that based on this kind of 0-D structure and exploring their photo-physical properties. By varying the species and
sizes of the organic or inorganic counterparts, we could effectively obtain 0-D ionic crystals with different crystal
structures and quantum-confinement effects. Moreover, we are confident to develop a series of materials that give
different but efficient emission behaviors for multiple applications.
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