Graphene/III–V Quantum Dot Mixed-Dimensional Heterostructure for Enhanced Radiative Recombinations via Hole Carrier Transfer

Abstract

Fabrication of high quantum efficiency nanoscale device is challenging due to increased carrier loss at surface. Low dimensional materials such 0D quantum dots and 2D materials have been widely studied to mitigate the loss. Here, we demonstrate a strong photoluminescence enhancement from graphene/III−V quantum dot mixed-dimensional heterostructures. The distance between graphene and quantum dots in the 2D/0D hybrid structure determines the degree of radiative carrier recombination enhancement from 80% to 800% compared to the quantum dot only structure. Time-resolved photoluminescence decay also shows increased carrier lifetimes when the distance decreases from 50 to 10 nm. We propose that the optical enhancement is due to energy band bending and hole carrier transfer, which repair the imbalance of electron and hole carrier densities in quantum dots. This 2D graphene/0D quantum dot heterostructure shows promise for high performance nanoscale optoelectronic devices.

Transfer of 2D Films: From Imperfection to Perfection

“…Beyond the realm of 2D films, the transfer, as mentioned earlier techniques, holds the potential for application across a wide spectrum of materials, such as perovskites, − III–V semiconductor materials, − ,− and more. An example of transferring MAPbI 3 and MAPbBrI 2 for photovoltaic applications using PDMS layers was executed by Mohapatra et al This approach demonstrates the versatility of the PDMS transfer method, facilitating the preparation of high-crystallinity perovskite materials with excellent surface coverage.…”

Rapid Crystallization and Fluorescence of Poly(ethylene terephthalate) Using Graphene Quantum Dots as Nucleating Agents

“…GQDs are a kind of new class of organic-inorganic hybrid nanoparticles with atomicscale graphite planes [23][24][25], usually 0.5-2 nm thick and less than 15 nm in diameter [26]. GQDs have many hydroxyl and carboxyl groups at their edges, which allow them to be more dispersed while retaining the physical and chemical properties of graphene, making them more soluble in solvents [27].…”

Manipulations of Electronic and Spin States in Co-Quantum Dot/WS2 Heterostructure on a Metal-Dielectric Composite Substrate by Controlling Interfacial Carriers

“…Compared with conventional materials, quantum dots (QDs) have a limited scale and novel electronic properties, such as quantum stochastic resonance, the Pauli spin blockade phenomenon, and giant anisotropic magnetoresistance, which offer a perfect physical platform for exploiting and controlling the charge and spin states. Moreover, the interfacial interaction between QDs and substrate materials could further produce peculiar physical phenomena. − In this regard, emerging two-dimensional (2D) van der Waals (vdW) heterostructures with QDs show tremendous potential to exploit their unique properties and provide a new strategy for designing spintronic devices.…”