Thermal, electrical and mechanical stabilities of a Cu wire-based transparent heater are improved by coating alumina and polymide films.

In this work, a high gain broadband photoconductor based on a wide bandgap amorphous gallium oxide film was reported. Meanwhile, a novel short-time heating method was demonstrated to effectively suppress the PPC effect.

Cesium‐lead‐halide perovskite quantum dots (PQDs), which have superior optical and electronic properties, are regarded as excellent materials for various optoelectronic devices. However, their unstable nature greatly hinders their practical application. Herein, a simple hydrolysis encapsulation method is developed to embed PQDs into mesoporous polystyrene microspheres (MPMs) followed by a silica shell covering process, which generates luminescent PQDs/MPMs@SiO2 hybrid microspheres with significantly enhanced stability. The obtained CsPbBr3‐PQDs/MPMs@SiO2 hybrid microspheres show a high photoluminescence quantum yield of 84%. More importantly, the MPMs@silica protective shells effectively cut off direct contact between outer erosive species and the inner embedded PQDs and modify the hybrid microspheres with ultralong alkyl chains for improved resistance to solvents and heat. Hence, these CsPbBr3‐PQDs/MPMs@SiO2 hybrid microspheres exhibit good chemical/physical stabilities, even when exposed to harsh environments, such as deionized water, isopropanol, acid/alkali solution, anion‐exchange reactions, and heating. Particularly, the water stability, which produced the remaining ≈48% proportion of the initial fluorescence intensity after a quite long aqueous storage period of 30 d, is the best reported among the stability‐related studies of PQDs. Meanwhile, white light‐emitting diodes (LEDs) are achieved by mixing green CsPbBr3‐PQDs/MPMs@SiO2 microspheres with red commercial phosphors on a blue chip. High power efficiency of 81 lm W−1 and good electroluminescence stability are obtained.

This review briefly covers several typical topics of ultrafast carrier dynamics in two-dimensional transition metal dichalcogenides (TMDs) such as many-body effects, ultrafast nonradiative recombination, intervalley transfer of carriers, high-energy C exciton cooling, and carrier dynamics in TMD-based heterostructures.

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Graphene oxide (GO)-based resistive-switching (RS) memories offer the promise of low-temperature solution-processability and high mechanical flexibility, making them ideally suited for future flexible electronic devices. The RS of GO can be recognized as electric-field-induced connection/disconnection of nanoscale reduced graphene oxide (RGO) conducting filaments (CFs). Instead of operating an electrical FORMING process, which generally results in high randomness of RGO CFs due to current overshoot, a TiO -assisted photocatalytic reduction method is used to generate RGO-domains locally through controlling the UV irradiation time and TiO concentration. The elimination of the FORMING process successfully suppresses the RGO overgrowth and improved RS memory characteristics are achieved in graphene oxide-TiO (Go-TiO ) nanocomposites, including reduced SET voltage, improved switching variability, and increased switching speed. Furthermore, the room-temperature process of this method is compatible with flexible plastic substrates and the memory cells exhibit excellent flexibility. Experimental results evidence that the combined advantages of reducing the oxygen-migration barrier and enhancing the local-electric-field with RGO-manipulation are responsible for the improved RS behaviors. These results offer valuable insight into the role of RGO-domains in GO memory devices, and also, this mild photoreduction method can be extended to the development of carbon-based flexible electronics.

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This paper presents an analytical model of resistive switching in organic-inorganic CH 3 NH 3 PbI 3 perovskite. It is interpreted that the resistive switching phenomenon is due to the formation/rupture of iodine vacancy-based conductive filament (CF) propagating in both vertical and lateral directions. Set and reset processes are explained in the model by the evolution of the CF length and radius driven by electrical and thermal forces. The model-based simulation results can describe the experimental results, providing an estimate of several switching parameters such as the activation energy of iodine vacancy migration and the CF diameter. Learning in a two-transistor/one-resistor synapse structure is demonstrated by simulations. Finally, the neuromorphic recognition of multiple patterns is demonstrated through a two-layer neural network consisting of 5625 presynaptic neurons and four postsynaptic neurons.