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Cesium-based perovskite nanocrystals (NCs) have outstanding photophysical properties improving the performances of lighting devices. Fundamental studies on excitonic properties and hot-carrier dynamics in perovskite NCs further suggest that these materials show higher efficiencies compared to the bulk form of perovskites. However, the relaxation rates and pathways of hot-carriers are still being elucidated. By using ultrafast transient spectroscopy and calculating electronic band structures, we

Direct partial oxidation of methane to liquid oxygenates has been regarded as a potential route to valorize methane. However, CH₄ activation usually requires a high temperature and pressure, which lowers the feasibility of the reaction. Here, we propose an electro-assisted approach for the partial oxidation of methane, using in-situ cathodically generated reactive oxygen species, at ambient temperature and pressure. Upon using acid-treated carbon as the electrocatalyst, the electro-as

A novel strategy to prepare organometallic halide perovskite quantum dots (OHP-QDs) in a polymer film can enhance both the structural stability and the optical properties.

Abstract In various organisms in nature, the energy‐dissipation layers within their adhesive systems are known to play a significant role in enhancement of adhesion performance in pulling and peeling directions. Reported here is that the pedal‐muscle structures of snails can be exploited to form a repeatable, microstructure‐embedded adhesive, enabling enhanced adhesion in both pulling (13 N cm −2 ) and peeling (20 J m −2 ) directions with excellent repeatability (<1000 cycles). The measured a

Abstract Cesium‐based perovskite nanocrystals (NCs) have outstanding photophysical properties improving the performances of lighting devices. Fundamental studies on excitonic properties and hot‐carrier dynamics in perovskite NCs further suggest that these materials show higher efficiencies compared to the bulk form of perovskites. However, the relaxation rates and pathways of hot‐carriers are still being elucidated. By using ultrafast transient spectroscopy and calculating electronic band struct

The optimal use of batteries in drones is a critical issue for achieving both reliable operation and maximum flight time. The key is to acquire accurate information about the state of charge (SoC) of the battery in runtime. Drones typically employ series-connected lithium-ion polymer (Li-Po) battery cells, whose SoC is affected by many environmental factors as well as flight patterns. In this article, we propose a scheme, called Optrone, which maximizes the flight time of a drone while safely us

This study presents the development and application of methodologies to support weather-responsive traffic management (WRTM) strategies by building on traffic estimation and prediction system models. First, a systematic framework for implementing and evaluating WRTM strategies under severe weather conditions is developed. This framework includes activities for planning, preparing, and deploying WRTM strategies in three different time frames: long-term strategic planning, short-term tactical plan

Mesoporous carbon derived from pyrolysis of metal–organic frameworks (MOFs) is advantageous owing to its high specific surface area, large pore volume, and versatility in both structure and composition. Heteroatom doping on mesoporous carbon by synthesizing with heteroatom containing ligands (pre-synthetic process) or incorporating heteroatom-containing compounds during pyrolysis (post-doping) can further enhance its electrochemical properties. Although both methods have been applied to increase

Although Group II-VI quantum dots (QDs) have attracted much attention due to their wide range of applications in QD-based devices, the presence of toxic ions in II-VI QDs raises environmental concerns. To fulfill the demands of nontoxic QDs, synthetic routes for III-V QDs have been developed. However, only a few comparative analyses on optical properties of III-V QDs have been performed. In this study, the composition-related energetic trap distributions have been explored by using three differe

Abstract Nitrogen‐doped porous carbon derived from various polymer precursors receives great attention for applications in supercapacitor electrodes due to its high specific area and fast ion transportation within the electrodes. The porous structure with high content of nitrogen atoms enhances the wettability and accelerates the diffusion of ions inside free‐standing electrodes. These electrodes are fabricated by carbonization of nitrogen‐rich carbon precursors such as polyimide and polyaniline