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Abstract Spider-capture-silk (SCS) can directionally capture and transport water from humid air relying on the unique geometrical structure. Although there have been adequate reports on the fabrication of artificial SCSs from petroleum-based materials, it remains a big challenge to innovate bio-based SCS mimicking fibers with high-performance fog collection ability and efficiency simultaneously. Herein, we report an eco-friendly and economical fiber system for water collection by coating gelatin on degummed silk. Compared to the previously reported fibers with the best fog collection ability (~ 13.10 μL), Gelatin on silk fiber 10 (GSF10) can collect larger water droplet (~ 16.70 μL in 330 s) with ~ 98% less mass. Meanwhile, the water collection efficiency of GSF10 demonstrates ~ 72% and ~ 48% enhancement to the existing best water collection polymer coated SCS fibers and spidroin eMaSp2 coated degummed silk respectively in terms of volume-to-TCL (vapor–liquid-solid three-phase contact line) index. The simultaneous function of superhydrophilicity, surface energy gradient, and ~ 65% water-induced volume swelling of the gelatin knots are the key factors in advancing the water collection performance. Abundant availability of feedstocks and ~ 75% improved space utilization guarantee the scalability and practical application of such bio-based fiber. Graphic Abstract

Scaling up anisotropic freeze-casting processes can be challenging due to the temperature gradient farther from the cold source. Here, authors report an additive freeze-casting technique able to produce large-scale aerogel panels and demonstrate it towards practical passive cooling applications.

Abstract With the mandate of worldwide carbon neutralization, pursuing comfortable living environment while consuming less energy is an enticing and unavoidable choice. Novel composite aerogels with super thermal insulation and high sunlight reflection are developed for energy-efficient buildings. A solvent-assisted freeze-casting strategy is used to produce boron nitride nanosheet/polyvinyl alcohol (BNNS/PVA) composite aerogels with a tailored alignment channel structure. The effects of acetone and BNNS fillers on microstructures and multifunctional properties of aerogels are investigated. The acetone in the PVA suspension enlarges the cell walls to suppress the shrinkage, giving rise to a lower density and a higher porosity, accompanied with much diminished heat conduction throughout the whole product. The addition of BNNS fillers creates whiskers in place of disconnected transverse ligaments between adjacent cell walls, further ameliorating the thermal insulation transverse to the cell wall direction. The resultant BNNS/PVA aerogel delivers an ultralow thermal conductivity of 23.5 mW m−1 K−1 in the transverse direction. The superinsulating aerogel presents both an infrared stealthy capability and a high solar reflectance of 93.8% over the whole sunlight wavelength, far outperforming commercial expanded polystyrene foams with reflective coatings. The anisotropic BNNS/PVA composite aerogel presents great potential for application in energy-saving buildings.

Abstract Background The psychological well-being of university students is an important factor in successfully coping with the demands of academic life. This study aimed to assess the impact of a peer-led intervention of mental health promotion combined with coping-strategy-based group workshops on mental health awareness and help-seeking behavior among university students in Hong Kong. Method A mixed-method concurrent design was used for this study. Quantitative data, based on one-group pretest-posttest design, were collected using Mental Health Knowledge Schedule Questionnaire to assess mental health awareness, and Attitude Towards Seeking Professional Help Questionnaire-Short Form to examine help-seeking behavior of university students from The Hong Kong Polytechnic University. Qualitative data were collected from written post-activity reflections and focus group discussions which were thematically analyzed. Results A total of 62 university students (mean age: 23.2 ± 5.1 years) were included in this study. Mental health awareness was significantly improved (p = 0.015, 95% Confidence Interval of − 2.670, − 0.297) after program implementation. Help-seeking behavior mean score increased from pretest to posttest, however, no significant difference was observed (p = 0.188, 95% CI = − 1.775, 0.355). Qualitative analysis revealed that the program helped participants learn about coping strategies to help themselves and others with mental health challenges. Conclusions The peer-led intervention provided a positive impact through increased mental health awareness and knowledge of coping strategies on self-help and helping others among university students. Further study could focus on the impact of the program when applied regularly throughout the entire academic year.