Characterization of atomic defects on the photoluminescence in two‐dimensional materials using transmission electron microscope

Abstract

Two‐dimensional material (2D) that possesses atomic thin geometry and remarkable properties is a star material for the fundamental researches and advanced applications. Defects in 2D materials are critical and fundamental to understand the chemical, physical, and optical properties. Photoluminescence arises in 2D materials owing to various physical phenomena including activator/dopant‐induced luminescence and defect‐related emissions, and so forth. With the advanced transmission electron microscopy (TEM) technologies, such as aberration correction and low voltage technologies, the morphology, chemical compositions and electronic structures of defects in 2D material could be directly characterized at the atomic scale. In this review, we introduce the applications of state‐of‐the‐art TEM technologies on the studies of the role of atomic defects in the photoluminescence characteristics in 2D material. The challenges in spatial and time resolution are also discussed. It is proved that TEM is a powerful tool to pinpoint the relationship between the defects and the photoluminescence characteristics.

A Noble Metal Dichalcogenide for High‐Performance Field‐Effect Transistors and Broadband Photodetectors

“…2D materials including graphene, transition metal dichalcogenides (TMDs), and black phosphorus (BP) with atomic thickness, high carrier mobility, and tunable bandgap have tremendous potential as the promising building blocks for the future electronic and optoelectronic devices . Graphene, as the pioneer of 2D materials, has exhibited abundant physical and chemical properties .…”

Aluminum nanocomposites reinforced with monolayer polyaniline (C3N): assessing the mechanical and ballistic properties

“…Therefore, it is important to investigate the effect of these defects on the properties of nanomaterials. 44,45 It should be noted that while the presence of defects in nanomaterials seems to be harmful if these defects are controlled in the structure, they may give rise to new properties such as the creation of a bandgap, which sometimes changes the system from insulator to metal. 46 In this work, three types of defects including vacancy, crack, and void defects were investigated.…”

Role of Optical Phonons in Bulk Molybdenum Diselenide Thermal Properties Probed by Advanced Raman Spectroscopy

“…Unlike graphene lacking bandgap, several TMDCs prove to possess sizable bandgaps around 1-2 eV, making them suitable for use in electronic and optoelectronic devices. [3][4][5][6] Molybdenum diselenide (MoSe 2 ) is one of the most studied TMDCs, and considerable device designs related to MoSe 2 have been proposed. [7][8][9][10] TE materials can directly convert heat into electrical energy, and their efficiency is determined by the dimensionless figure of merit ZT (ZT ¼ S 2 σT/κ), where S is the Seebeck coefficient, σ is the electrical conductivity, T is the absolute temperature, and κ is the thermal conductivity.…”