InP/ZnS quantum dot photoluminescence modulation via in situ H2S interface engineering.

InP quantum dots (QDs) are attracting significant interest as a potentially less toxic alternative to Cd-based QDs in many research areas. Although InP-based core/shell QDs with excellent photoluminescence properties have been reported so far, sophisticated interface treatment to eliminate defects is often necessary. Herein, using aminophosphine as a seeding source of phosphorus, we find that H2S can be efficiently generated from the reaction between a thiol and an alkylamine at high temperatures. Apart from general comprehension that H2S acts as a S precursor, it is revealed that with core etching by H2S, the interface between InP and ZnS can be reconstructed with S2- incorporation. Such a transition layer can reduce inherent defects at the interface, resulting in significant photoluminescence (PL) enhancement. Meanwhile, the size of the InP core could be further controlled by H2S etching, which offers a feasible process to obtain wide band gap InP-based QDs with blue emission.

Barium titanate-enhanced hexagonal boron nitride inks for printable high-performance dielectrics.

Printed electronics have been attracting significant interest for their potential to enable flexible and wearable electronic applications. Together with printable semiconductors, solution-processed dielectric inks are key in enabling low-power and high-performance printed electronics. In the quest for suitable dielectrics inks, two-dimensional materials such as hexagonal boron nitride (h-BN) have emerged in the form of printable dielectrics. In this work, we report barium titanate (BaTiO3) nanoparticles as an effective additive for inkjet-printable h-BN inks. The resulting inkjet printed BaTiO3/h-BN thin films reach a dielectric constant (εr) of âˆ¼16 by adding 10% of BaTiO3nanoparticles (in their volume fraction to the exfoliated h-BN flakes) in water-based inks. This result enabled all-inkjet printed flexible capacitors withC âˆ¼ 10.39 nF cm-2, paving the way to future low power, printed and flexible electronics.

Fibre electronics: towards scaled-up manufacturing of integrated e-textile systems.

The quest for a close human interaction with electronic devices for healthcare, safety, energy and security has driven giant leaps in portable and wearable technologies in recent years. Electronic textiles (e-textiles) are emerging as key enablers of wearable devices. Unlike conventional heavy, rigid, and hard-to-wear gadgets, e-textiles can lead to lightweight, flexible, soft, and breathable devices, which can be worn like everyday clothes. A new generation of fibre-based electronics is emerging which can be made into wearable e-textiles. A suite of start-of-the-art functional materials have been used to develop novel fibre-based devices (FBDs), which have shown excellent potential in creating wearable e-textiles. Recent research in this area has led to the development of fibre-based electronic, optoelectronic, energy harvesting, energy storage, and sensing devices, which have also been integrated into multifunctional e-textile systems. Here we review the key technological advancements in FBDs and provide an updated critical evaluation of the status of the research in this field. Focusing on various aspects of materials development, device fabrication, fibre processing, textile integration, and scaled-up manufacturing we discuss current limitations and present an outlook on how to address the future development of this field. The critical analysis of key challenges and existing opportunities in fibre electronics aims to define a roadmap for future applications in this area.

Wearable solid-state capacitors based on two-dimensional material all-textile heterostructures.

Two-dimensional (2D) materials are a rapidly growing area of interest for wearable electronics, due to their flexible and unique electrical properties. All-textile-based wearable electronic components are key to enable future wearable electronics. Single component electrical elements have been demonstrated; however heterostructure-based assemblies, combining electrically conductive and dielectric textiles such as all-textile capacitors are currently missing. Here we demonstrate a superhydrophobic conducting fabric with a sheet resistance Rs∼ 2.16 kΩ□-1, and a pinhole-free dielectric fabric with a relative permittivity εr∼ 2.35 enabled by graphene and hexagonal boron nitride inks, respectively. The different fabrics are then integrated to engineer the first example of an all-textile-based capacitive heterostructure with an effective capacitance C ∼ 26 pF cm-2 and a flexibility of ∼1 cm bending radius. The capacitor sustains 20 cycles of repeated washing and more than 100 cycles of repeated bending. Finally, an AC low-pass filter with a cut-off frequency of ∼15 kHz is integrated by combining the conductive polyester and the capacitor. These results pave the way toward all-textile vertically integrated electronic devices.