Synthesis of WO_n‐WX₂ (n=2.7, 2.9; X=S, Se) Heterostructures for Highly Efficient Green Quantum Dot Light‐Emitting Diodes

Abstract

Preparation of two-dimensional (2D) heterostructures is important not only fundamentally, but also technologically for applications in electronics and optoelectronics. Herein, we report a facile colloidal method for the synthesis of WO -WX (n=2.7, 2.9; X=S, Se) heterostructures by sulfurization or selenization of WO nanomaterials. The WO -WX heterostructures are composed of WO nanoparticles (NPs) or WO nanowires (NWs) grown together with single- or few-layer WX nanosheets (NSs). As a proof-of-concept application, the WO -WX heterostructures are used as the anode interfacial buffer layer for green quantum dot light-emitting diodes (QLEDs). The QLED prepared with WO NP-WSe NS heterostructures achieves external quantum efficiency (EQE) of 8.53 %. To our knowledge, this is the highest efficiency in the reported green QLEDs using inorganic materials as the hole injection layer.

A Complementary Co−Ni Phosphide/Bimetallic Alloy‐Interspersed N‐Doped Graphene Electrocatalyst for Overall Alkaline Water Splitting

“…The adverse effects of fossil fuels on the energy supply and environment have accelerated efforts to foster renewable energy technologies, such as metal−air batteries, water splitting, and fuel cells [1] . Among these, hydrogen production through electrocatalytic water splitting has provided a solution for clean energy demand owing to its environment benignity, renewability, high pure H 2 production, and has the potential for large‐scale commercialization [2,3] .…”

The highly-efficient light-emitting diodes based on transition metal dichalcogenides: from architecture to performance

“…100 The strong inter-exciton interactions in 1L-TMDCs were considered to be the primary limiting factor of QY. 29,101 The strong coulombic interactions between excitons induced an exciton-exciton annihilation (EEA) effect, in which excitons decayed in a nonradiative way. 29 Therefore, the density of radiative excitons was reduced.…”

Efficient Tandem Quantum‐Dot LEDs Enabled by An Inorganic Semiconductor‐Metal‐Dielectric Interconnecting Layer Stack

“…Aqueous PEDOT:PSS degrades the performance of the underlying devices, a result of its hygroscopic nature. [ 18,19 ] In recent years, efforts have been devoted to replacing PEDOT:PSS with inorganic metal‐oxides such as tungsten oxide (WO 3 ), molybdenum oxide (MoO x ), nickel oxide (NiO), and vanadium oxides (V 2 O 5 ). [ 20–23 ]…”

“…Aqueous PEDOT:PSS degrades the performance of the underlying devices, a result of its hygroscopic nature. [18,19] In recent years, efforts have been devoted to replacing PEDOT:PSS with inorganic metal-oxides such as tungsten oxide (WO 3 ), molybdenum oxide (MoO x ), nickel oxide (NiO), and vanadium oxides (V 2 O 5 ). [20][21][22][23] Ultrathin metals (e.g., Al and Ag) inserted between the electron transport layer (ETL) and hole transport layer (HTL) have been proven to facilitate electron generation and separation at the ICL, enabling increased performance in tandem LEDs and solar cells.…”