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Summary: Organic‐inorganic hybrid perovskites have caused great interest owing to their ever‐increasing power conversion efficiencies and extensive application prospects. However, the instability under ambient environment hinders their large‐scale commercialization. In this paper, the geometries, electronic structures, photoelectric properties, and stabilities of FAPbI3 (001) surfaces, graphene sheet, and graphene/FAPbI3 heterojunctions were explored using first‐principles calculations. Our calculated results show that a stable heterojunction can be constructed from graphene sheet and FAPbI3 (001) surface by van der Waals interaction. The construction of heterojunction has little influence on the effective masses of carriers, band structure, and optical absorbance of the perovskites. The graphene sheet of heterojunction can block the infiltration of O2 and H2O molecules and protect the perovskite from the degradation in light and humid air. Therefore, assembling a heterojunction from graphene sheet and FAPbI3 surface is an effective strategy for improving the stability and photoelectric properties of perovskite materials. Our study provides an atomic‐level insight into the fundamental properties of the graphene/FAPbI3 heterojunctions and a guideline for designing more stable perovskite solar cells. [ABSTRACT FROM AUTHOR]

Aim(s): To construct structural equation models to test the mediating role of emotional intelligence in the relationship between mindfulness and occupational burnout. Background: Reports assessing the relationships among mindfulness, emotional intelligence and burnout, specifically in ICU nurses, are scarce. Methods: This was a descriptive, correlational, cross‐sectional research design with 883 ICU nurses enrolled by convenience sampling from 29 ICUs in seven tertiary hospitals in urban areas of Chengdu, China. Mediation analysis was performed by structural equation modelling. Indirect effects were evaluated through bootstrapping. Results: The associations among mindfulness, emotional intelligence, emotional exhaustion, depersonalization and personal accomplishment were all significant (p <.001). In the mediation models, emotional intelligence partially mediates the relationships between mindfulness and emotional exhaustion (indirect effect 0.118, p =.006; direct effect −0.374, p =.010; total effect −0.492, p =.011) and between mindfulness and depersonalization (indirect effect −0.182, p =.006; direct effect −0.452, p =.015; total effect −0.633, p =.018). Emotional intelligence plays a total mediating role between mindfulness and personal accomplishment (indirect effect 0.293, p =.004; direct effect 0.119, p =.053). Conclusions: The results suggest that nursing manager could implement mindfulness training to improve occupational burnout in ICU nurses. Implications for Nursing Management: Nursing managers could help create a more favourable working environment by providing mindfulness training. Such mindfulness training could help improve nursing quality, reduce errors and ensure patient safety, possibly improving patient prognosis and probably satisfaction. [ABSTRACT FROM AUTHOR]

Summary: The power conversion efficiency of organic‐inorganic hybrid perovskite solar cells (PSCs) has exceeded 25%, but the instability limited their practical applications. In this paper, we report a comprehensive study on a Sn‐ and Sr‐mixed lead‐free perovskites, MASn1−xSrxI3(x = 0, 0.25, 0.5, 0.75, 1), by using the first‐principles calculations based on the density functional theory. The crystal structures, band gaps, surface properties, and the adsorptions of oxygen and water molecules on the surfaces of the materials were analyzed and discussed. Our results show that the lattice constants and band gaps of MASn1−xSrxI3 become larger with the increase of Sr components. The band gap of MASrI3 is 4.16 eV, which is too large to be suitable as an efficient photo absorber in the solar cell, but one of the half substituted compounds, MASn0.5Sr0.5I3, has an adequate band gap of 1.37 eV. Both oxygen and water molecules prefer to adsorb on the metal sites (Sn and Sr), and Sr atom has larger attractive ability to oxygen and water molecules than Sn atom. The adsorptions of water on metal atoms are stronger than that of oxygen molecule. The charge transfer from Sn atom to O2/H2O molecule is larger than that from Sr to the adsorbate in the adsorption process, meaning that Sn atom is easier to be oxidized than Sr atom in the air condition. The adsorption energies for O2/H2O adsorbed on clean, and H2O/O2 preadsorbed surfaces are comparable, indicating that the already adsorbed molecule does not exclude the upcoming molecule. So, we predict that a stable Sn‐ and Sr‐mixed PSC material with a suitable band gap can be obtained through the substitution of Sn atom in MASnI3 by Sr atom, and the addition of Sr atom would protect Sn atom from the oxidation to a certain extent. This study is expected to be helpful for further experiments to find new kinds of possible lead‐free perovskite materials. [ABSTRACT FROM AUTHOR]