Advances in Two-Dimensional Materials for Optoelectronics Applications

Abstract

The past one and a half decades have witnessed the tremendous progress of two-dimensional (2D) crystals, including graphene, transition-metal dichalcogenides, black phosphorus, MXenes, hexagonal boron nitride, etc., in a variety of fields. The key to their success is their unique structural, electrical, mechanical and optical properties. Herein, this paper gives a comprehensive summary on the recent advances in 2D materials for optoelectronic approaches with the emphasis on the morphology and structure, optical properties, synthesis methods, as well as detailed optoelectronic applications. Additionally, the challenges and perspectives in the current development of 2D materials are also summarized and indicated. Therefore, this review can provide a reference for further explorations and innovations of 2D material-based optoelectronics devices.

Two-dimensional Janus MGeSiP4 (M = Ti, Zr, and Hf) with an indirect band gap and high carrier mobilities: first-principles calculations

“…The presence of an unconventional asymmetric sandwich structure in two-dimensional (2D) materials results in an internal vertical electric field (E) and breaking of mirror inversion symmetry, leading to novel properties. 1,2 Owing to their tunable electronic structures with widely ranging electrical conductivity, from that of metals, to semiconductors and insulators, 2D materials have shown promise for various applications, including in nanoelectronics, 3,4 optoelectronics, 5,6 catalysis, 7,8 and sensors. 9 Therefore, they have attracted widespread research interest in recent years.…”

Ferroelectric Tuning of ZnO Ultraviolet Photodetectors

“…R can be expressed as R = ∆I/(PA), where ∆I = I illuminated − I dark ; I illuminated and I dark are the photocurrent and dark current, respectively; P is the power density of the incident light; and A is the light-receiving area. We calculated the responsivity of the three states in Figure 2e, and the R of the device was 2.40 × 10 4 A/W in the Down state at V DS = 0.1 V with P = 50 mW/cm 2 .…”

“…UV rays significantly impact human health and the ecological environment, and UV photodetectors are widely used in infrastructure, military facilities, and scientific research. Therefore, it is very important to develop UV photodetectors with high photodetection performance and low power consumption [1,2].…”

Functionality-Dependent Electrical Conductivity in Two-Dimensional Covalent Organic Frameworks

“…Ever since the discovery of graphene, a great deal of research interest has been devoted to the development of 2D materials consisting of unique optical and electrical properties, including superconductivity, high charge carrier mobility, and mechanical flexibility. , The diverse physical and chemical properties of these layered structures, e.g., graphene, transition-metal dichalcogenides (TMDCs), and MXenes, drive their utilization in electronics, catalysis, and biosensing . On the other hand, porous materials such as metal–organic frameworks (MOFs) , and COFs with structural tunability, high surface areas, and permanent and periodic porosity (with adjustable pore sizes) have emerged as promising materials for a wide range of applications in gas storage and separation, drug delivery, sensing, energy storage, and conversion. − Benefiting from 2D materials and porous structures, the 2D COFs with an unprecedented diversity of linkers and linkages, well-defined reactive sites, and regular nanochannels manifested alternative pathways for efficient mass and charge transfer. − In particular, 2D conjugated COFs add paramount significance owing to extended π-conjugation in the 2D plane and columnar arrays of π–π stacking between successive COF layers through the rational tuning of building blocks .…”

“…1,2 The diverse physical and chemical properties of these layered structures, e.g., graphene, transition-metal dichalcogenides (TMDCs), and MXenes, drive their utilization in electronics, catalysis, and biosensing. 3 On the other hand, porous materials such as metal−organic frameworks (MOFs) 4,5 and COFs with structural tunability, high surface areas, and permanent and periodic porosity (with adjustable pore sizes) have emerged as promising materials for a wide range of applications in gas storage and separation, drug delivery, sensing, energy storage, and conversion. 6−15 Benefiting from 2D materials and porous structures, the 2D COFs with an unprecedented diversity of linkers and linkages, welldefined reactive sites, and regular nanochannels manifested alternative pathways for efficient mass and charge transfer.…”