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.

Two-dimensional (2D) materials including graphene, hexagonal boron nitride (h-BN), and transition metal dichalcogenides (TMDCs) have revolutionized electronic, optoelectronic and spintronic devices. Recent progress has been made in the knowledge of spin injection, detection, and manipulation utilizing spintronic devices based on 2D materials. However, some bottlenecks still need to be addressed to employ spintronic devices for logical applications. Here, we review the major advances and progress in vertical magnetic tunnel junctions (MTJs) made of various 2D materials as spacer layers between distinct ferromagnetic electrodes. Spin transportation characteristics depending on the magnetic field are investigated by considering the magnetoresistance (MR) and tunneling magnetoresistance (TMR) ratio in vertically stacked structures. This review examines the important features of spin transfer through the various spacer 2D materials in MTJs by carefully analyzing the temperature-dependent phenomena. The underlying physics, reliance of spin signals on temperature, quality of junction, and various other parameters are discussed in detail. Furthermore, newly discovered 2D ferromagnets introduce an entirely new type of van der Waals junction enabling effective dynamic control and spin transport across such heterojunctions. Finally, the challenges and prospects of 2D materials-based spin-valve MTJs for improving spintronic devices are discussed in detail.

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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