Approaching Bulk Mobility in PbSe Colloidal Quantum Dots 3D Superlattices

Abstract

Abstract3D superlattices made of colloidal quantum dots are a promising candidate for the next generation of optoelectronic devices as they are expected to exhibit a unique combination of tunable optical properties and coherent electrical transport through minibands. While most of the previous work was performed on 2D arrays, the control over the formation of these systems is lacking, where limited long‐range order and energetical disorder have so far hindered the potential of these metamaterials, giving rise to disappointing transport properties. Here, it is reported that nanoscale‐level controlled ordering of colloidal quantum dots in 3D and over large areas allows the achievement of outstanding transport properties. The measured electron mobilities are the highest ever reported for a self‐assembled solid of fully quantum‐confined objects. This ultimately demonstrates that optoelectronic metamaterials with highly tunable optical properties (in this case in the short‐wavelength infrared spectral range) and charge mobilities approaching that of bulk semiconductor can be obtained. This finding paves the way toward a new generation of optoelectronic devices.

Stop Blaming Hopping Conduction in Nanocrystal Arrays, Use it for Active Photonics!

“…[26] Nevertheless, from a mobility perspective, it appears that such necked arrays do not provide significant benefits compared to disordered arrays of the same materials. [27][28][29][30][31][32] In the low mobility regime, hopping conduction is the wellestablished model for conduction in a NC array. [33][34][35] In this mechanism, charge carriers go from one NC to the next by quantum tunneling.…”

Two‐Step Sequential Process for Fabricating Graphene Nanosheets Decorated with Copper Halide Nanocrystals and Their Optoelectronic Applications

“…[ 3 ] Furthermore, in the process of creating nanohybrids, the usual synthetic variables as well as additional material variables can be considered, [ 4,5 ] which open up possibilities for exploring a broader range of new scientific phenomena. Diverse nanoscale materials with specific functionalities, such as exceptional electrical and optical properties, [ 6–8 ] have been designed or discovered for both academic research and industrial applications. [ 9–11 ]…”

“…[3] Furthermore, in the process of creating nanohybrids, the usual synthetic variables as well as additional material variables can be considered, [4,5] which open up possibilities for exploring a broader range of new scientific phenomena. Diverse nanoscale materials with specific functionalities, such as exceptional electrical and optical properties, [6][7][8] have been designed or discovered for both academic research and industrial applications. [9][10][11] Inorganic lead halide nanocrystals with exceptional optical and electronic properties are garnering interest as key components in a variety of optical, optoelectronic, catalytic, and imaging applications.…”

InAs Nanorod Colloidal Quantum Dots with Tunable Bandgaps Deep into the Short-Wave Infrared

“…Colloidal quantum dots (CQDs) are becoming increasingly important in various semiconductor-based cutting-edge technologies due to their solution processability, which offers design versatility and reduces the complexity of device fabrication. − In particular, CQDs that absorb in the infrared (IR) region, especially the short-wave infrared (SWIR; λ ∼ 1200–3000 nm) absorbers, are expected to play important roles in optical communication, night vision, advanced driver-assistance systems, medical imaging, and food processing. − Unfortunately, the availability of CQDs active in the IR range is considerably limited compared to those active in the visible range. , Moreover, most of the studied IR-active CQDs are based on heavy toxic metals like Hg and Pb (such as II–VI and VI–VI semiconductors), which is a major obstacle toward their adoption. ,− Recently, III–V semiconductor CQDs have emerged as potential environmentally friendly alternative material systems for IR applications. ,, Their advantages stem from the absence of heavy toxic metals and their large Bohr exciton radius, which in theory should afford bandgap tunability over a wider IR spectral range . Additionally, III–V semiconductors have direct bandgaps, high charge carrier mobilities, and low effective masses, all of which are critical parameters for fabricating high-performance optoelectronic devices. ,− …”