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NaNbO 3 is explored as a potential candidate for catalysis due to its excellent piezoelectricity. However, its photocatalysis is significantly limited for the inherent characteristics of wide band gap. In this work, NaNbO 3 and Ag dots-modified NaNbO 3 micron-sized powders are prepared and applied in piezo-photocatalysis to explore the coupling effects. The results show that the piezocatalysis degradation efficiency of RhB solution (the initial concentration C 0 = 5 mg/L) reaches 92.3% within 30 min, and the rate constant k is 0.0889 min−1. The efficiency of piezo-photocatalysis degradation reaches 92.7% in 25 min, and the rate constant k is 0.11 min−1 for NaNbO 3. The rate constant k of Ag dots-modified NaNbO 3 for piezo-photocatalytic degradation of RhB (C 0 = 5 mg/L) is increased to 0.16314 min−1. The optical and electrochemical activities of NaNbO 3 -0.75hAg are studied to reveal the role of Ag nanoparticles. The band gap of NaNbO 3 is 3.59 eV, which is decreased to 3.36 eV after the modification with Ag dots. The lower band gap means that e− in the valence band is more easily excited to shift the conduction band, which is beneficial to the photocatalytic reaction process. In addition, NaNbO 3 -0.75hAg has a higher photogenerated carrier density, a faster electron-hole pair separation and transfer rate, which are beneficial to the catalytic oxidation process. The work provides a useful means to decease the band gap of NaNbO 3 and achieve outstanding piezo-photocatalysis for degradation of hazardous organic dyes in contaminated water. [ABSTRACT FROM AUTHOR]

• Nursing staff experienced high levels of stress during the COVID-19 pandemic. • The main stressors were associated with staff roles and responsibilities, worries about resident and staff safety, and the heavy workloads. • Nursing staff perceived that effective coping strategies included approachability of management, peer support, and teamwork. • Nursing assistants required more practical guidance regarding COVID-19 prevention and control measures and relationship building with residents and their families. First-line nursing staff are responsible for protecting residents, the most vulnerable population, from COVID-19 infections. They are at a high risk of being infected with COVID-19 and experience high levels of psychological distress. To explore the challenges and coping strategies perceived by nursing staff during the COVID-19 pandemic in China. In April,2020, we conducted a qualitative study using in-depth semi-structured interviews with nursing staff. Participants were selected from seven nursing homes in three cities in Hunan Province, China. A total of 21 nursing staff participated in the study, including seven nurse managers, seven registered nurses and seven nursing assistants. Three main themes were identified. Different groups encountered different sources of stress and adopted various coping strategies to fulfil their responsibilities. Nursing home staff were underprepared for dealing with COVID-19-related challenges. Educational programs to improve the ability to deal with COVID-19 prevention and control are needed. [ABSTRACT FROM AUTHOR]

In previous studies, it has been shown that phosphorus and phosphate can improve the conductivity, change the electronic structure, and accept electrons from catalysts. In this study, we obtained phosphorylated NiAl-layered double hydroxide (P-LDH) nanosheets and used them as a novel cocatalyst in photocatalytic hydrogen evolution. After assembly with g-C 3 N 4 via an in situ process, these noble-metal-free composite photocatalysts showed superior photocatalytic hydrogen evolution activity. It was also found that the efficiency of H 2 production on the optimal composite was 1.5 times that of Pt-modified g-C 3 N 4. Characterization of the photocatalysts revealed that the effects of P-LDH were different from those of other bimetallic LDHs, showing a lower overpotential and faster reaction kinetics of H 2 evolution. Moreover, it was found that P-LDH has a higher surface work function than that of g-C 3 N 4 , leading to the formation of an interfacial electric field from CN toward P-LDH. Therefore, modifying P-LDH can efficiently improve the interfacial charge transfer rate, suppress photogenerated charge recombination, and lower the surface overpotential of g-C 3 N 4. This study serves as guidance on the design of more effective cocatalysts for photocatalytic hydrogen evolution reactions. • Novel phosphorylated NiAl-layered double hydroxide nanosheets were synthesized. • The P-LDH can act as a cocatalyst for photocatalytic hydrogen production. • The formation and effects of P-LDH were studied and verified in detail. [ABSTRACT FROM AUTHOR]

The development of lead-free ferroelectric ceramics exhibiting a high Curie point is regarded as a key aspect of improving the overall performance of high temperature sensing devices. Two-layer Dion-Jacobson phases have great potential for these applications, but the dielectric properties of many of these compounds have not been investigated and several are still erroneously considered to be non-polar. RbPrNb 2 O 7 , a two-layer Dion-Jacobson phase, has previously been identified as being non-polar at room temperature, with an orthorhombic crystal structure in space group Imma. Here, the structure of RbPrNb 2 O 7 is re-examined and its ferroelectric (FE) character confirmed through ferroelectric, dielectric and piezoelectric measurements, using dense bulk ceramics. In addition, the microstructure and phase evolution of the compound were analysed by transmission electron microscopy, variable temperature X-ray powder diffraction and differential scanning calorimetry. RbPrNb 2 O 7 is a ferroelectric at room temperature, exhibiting orthorhombic symmetry in space group I 2 cm. It undergoes a reversible FE ↔ FE phase transition at around 260 °C, with evidence for a diffuse apolar transition between 800 and 900 °C. Details of the subtle structural changes occurring at these transitions are discussed. RbPrNb 2 O 7 possesses a high Curie point of ~1090 °C, making it a potential candidate for use in high temperature piezoelectric sensing. Image, graphical abstract [ABSTRACT FROM AUTHOR]