The recent COVID-19 pandemic has been disrupting the daily lives of people across the world, causing a major concern for psychological well-being in children. This study aimed to examine (1) how life satisfaction and its potential predictors have been affected by the pandemic among school-aged children in Korea, and (2) which factors would predict their life satisfaction during the pandemic. We surveyed 166 fourth-graders in the Seoul metropolitan area to assess their psychological well-being and potentially related variables during the pandemic. The data were compared with those available from two pre-COVID-19 surveys, the 2018 Korean Children and Youth Panel Survey (n = 1236) and the 2019 Korean Children and Youth Well-being Index Survey (n = 334). Higher levels of stress were observed in children during the COVID-19 pandemic; however, the level of their life satisfaction remained unchanged when compared with data from the pre-COVID-19 surveys. The pandemic also affected peer relationship quality and susceptibility to smartphone addiction, but not perceived parenting style nor academic engagement. Interestingly, peer relationship quality no longer predicted life satisfaction during the pandemic; perceived parenting styles and parent-child conversation time predicted life satisfaction. The results suggest a central role of parent-child relationship in supporting the psychological well-being of school-aged children during the pandemic.

More active electrocatalysts for H2 and O2 evolution reactions, efficient membranes, and robust porous transport layers (PTL) are required for designing advanced proton exchange membrane water electrolysis (PEMWE) systems. An N‐doped carbon matrix is introduced in this study to surpass the existing Ti PTLs. One‐step pyrolysis results in the carbonization of polyaniline films to the N‐doped carbon matrix, simultaneous formation of desiccation cracks and IrxRuy nanoparticles, and partial impregnation of the synthesized particles into the carbon matrix. The embedded IrxRuy nanoparticles are firmly bound to the surface of the carbon matrix, inhibiting the dissolution and detachment of the nanoparticles during the O2 evolution reaction (OER). The cracks in the carbon matrix allow the steady transport of the produced O2, comparable to conventional PTLs. After optimizing the Ir and Ru contents of the nanoparticles based on the electrocatalytic performance, Ir88Ru12 embedded in the N‐doped carbon matrix is found to be the most suitable catalyst for enhancing the OER performance of the PEMWE system with negligible degradation. These findings can potentially contribute to the industrial application of PEMWE. Relevant electrochemical systems with membrane electrode assemblies, such as fuel cells and CO2 reduction systems, can be modified using the suggested structure.

Enwrapping metal nanoparticles with a carbon shell is a promising method for enhancing the stability of metal catalysts. However, carbon shell thickness control has not been studied extensively. In this study, a Pt catalyst with a carbon shell was synthesized, and the thickness of the carbon shell was controlled via the partial oxidation of the carbon layer. During the cooling step of the carbonization process, various concentrations of oxygen were supplied, and changes in the layer thickness were investigated according to the oxygen concentration. The thickness and characteristics of the carbon shell were examined using transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy. The results revealed that the thickness and surface properties of the carbon layer depend on the oxygen concentration. To determine the effect of the carbon shell thickness on the electrochemical characteristics of the catalyst, the activity and durability of the catalyst were studied via an oxygen reduction reaction and an accelerated stress test in both a half-cell and unit cell. Overall, the thin carbon shell enabled the Pt catalyst to maintain its activity and stability, while reducing the activation time required to achieve optimal performance.

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Direct urea fuel cells have been recognised as a potential approach for sustainable development. However, the low catalytic activity of urea oxidation has hindered its practical application. Herein, by employing...