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Heterojunctions underpin the design and performance of virtually all devices based on conventional semiconductors. While metal halide perovskites have received intense attention for applications in...

High-performance antifog coatings are critical for devices operating in high-humidity environments, such as endoscopes. However, existing antifog coatings have been unable to achieve good antifoggi...

Zeolites are microporous crystalline materials widely used in catalysis and adsorption applications. The fabrication of zeolite thin films and membranes has also opened up the possibility of using zeolites in electronic devices and membrane separations. The existing approach to growing zeolite films involves exposing the substrate to a high-pH environment; however, this process is applicable to only specific types of substrates. Our group has developed the direct wet deposition of zeolites via ultrasonic nozzle spray deposition to address this issue; however, the relationship between wetting properties and thin-film quality has yet to be investigated. In this study, we prepared zeolite CHA (Si:Al:P = 3:10:20) suspensions using different solvents and surfactants in various concentrations. We then examined the relationships among the composition of the cast solution, their wetting behavior on the glass substrate, and the uniformity of the resulting thin films. We found that using ethanol as a solvent with zeolite crystals in low concentrations with added surfactant yielded zeolite films of high quality. We were also able to produce low-haze zeolite coatings on glass. The zeolite coatings with high hydrophilicity and adsorption capacity presented excellent antifogging capability.

Zeolites are strongly hydrophilic materials that are widely used as water adsorbents. They are also promising candidates for antifogging coatings; however, researchers have yet to devise a suitable method for coating glass substrates with zeolite-based films. Here, we report on a direct wet deposition technique that is capable of casting zeolite films on glass substrates without exposing the glass to highly basic solutions or the vapors used in zeolite synthesis. We began by preparing cast solutions of pure silica zeolite MFI synthesized in hydrothermal reactions of various durations. The solutions were then applied to glass substrates via spin-on deposition to form zeolite films. The resulting zeolite MFI thin films were characterized in terms of transmittance to visible light, surface topography, thin film morphology, and crystallinity. Wetting and antifogging properties were also probed. We found that hydrophilicity and antifogging capability increased with the degree of thin film crystallinity. We also determined that the presence of the amorphous silica in the thin films is critical to transparency. Fabricating high-performance zeolite-based antifogging coatings requires an appropriate composition of zeolite crystals and amorphous silica.

Zeolite thin films with ordered nanopores and a low dielectric constant can serve as an insulation layer in microelectronic devices. However, the absence of a high-throughput deposition technique is a major technical hurdle in the industrial-scale production of zeolite thin films. Herein, we report on a scalable method, ultrasonic nozzle spray deposition (UNSD), which addresses this issue. A high-frequency standing wave introduced by the ultrasonic nozzle produces uniform sized droplets of the cast suspensions at a scale of tens to hundreds of micrometers, which results in a uniform thin film following the removal of the solvent. In this paper, we focus on the deposition of thin films comprising pure-silica zeolite MFI on a silicon wafer substrate. We systematically investigated how the quality of the zeolite thin films is affected by the composition of the cast suspensions and UNSD operating parameters. We identified the UNSD operating window that allows for the fabrication of uniform dense zeolite thin films at thicknesses ranging from hundreds of nanometers to 3 μm. We determined that zeolite MFI thin films prepared using UNSD outperformed those fabricated using conventional spin-on deposition in terms of uniform film thickness, low leakage current, and high Young's modulus.

This research integrated value congruence and person–environment fit theories into a validation of the effects of developmental and reward-based interventions on frontline service employees' commitment to service quality (FLSE CSQ). Based on a dyad survey conducted in 36 Starbucks stores in Taipei, the results reveal that formal training, coaching and rewards have positive relationships with FLSE CSQ. Moreover, FLSE CSQ is positively related to job satisfaction, commitment to the organisation, job performance and organisational citizenship behaviours (OCBs). The associations of development interventions and rewards with FLSE CSQ and the relationships of FLSE CSQ with job performance and OCBs are significantly stronger when the consistency of CSQ is high.