Polymer-dispersed liquid crystals (PDLCs), an indispensable class of electrically switchable materials, where nano- or microsized liquid crystal (LC) droplets are phase-separated from the polymer matrix, have been widely used in the fabrication of highly efficient and systematic smart windows. In this paper, we explored the effect of the photoinitiator concentration on the morphology and electro-optical properties of PDLC films based on thiol and acrylates. We prepared PDLC films using various concentrations of the photoinitiator, while keeping the concentrations of LC and monomers constant. We observed that the concentration of the photoinitiator directly influences the phase separation process, which in turn determines the morphology and electro-optical characteristics of the PDLC film. Thus, an optimized amount of the photoinitiator is required to prepare PDLC films with high transmittance and low switching time, haze, and power consumption. The optimized photoinitiator concentration can have a transmittance ΔT (difference between on- and off-state transmittances) of >85% at a low driving voltage.

Due to its semiconducting nature, controlled growth of large-area chemical vapor deposition (CVD)-grown two-dimensional (2D) molybdenum disulfide (MoS 2 ) has a lot of potential applications in photodetectors, sensors, and optoelectronics. Yet the controllable, large-area, and cost-effective growth of highly crystalline MoS 2 remains a challenge. Confined-space CVD is a very promising method for the growth of highly crystalline MoS 2 in a controlled manner. Herein, we report the large-scale growth of MoS 2 with different morphologies using NaCl as a seeding promoter for confined-space CVD. Changes in the morphologies of MoS 2 are reported by variation in the amount of seeding promoter, precursor ratio, and the growth temperature. Furthermore, the properties of the grown MoS 2 are analyzed using optical microscopy, scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDX), and atomic force microscopy (AFM). The electrical properties of the CVD-grown MoS 2 show promising performance from fabricated field-effect transistors. This work provides new insight into the growth of large-area MoS 2 and opens the way for its various optoelectronic and electronic applications.

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The long mean free path close to a micrometer in encapsulated graphene enabled us to rectify currents ballistically at room temperature. In this study, we introduce a ballistic rectifier that resembles a diode bridge and is based on graphene encapsulated using hexagonal boron nitride. Our device's asymmetric geometry combined with the exploitation of the ratcheting effect means that it can operate successfully and provides excellent performance. The device's estimated responsivities at 38 000 V/W for holes and 23 000 V/W for electrons at room temperature are among the highest values for a ballistic device reported to date.