Here we report the fabrication of dye-doped polymer-stabilized liquid crystals (PSLC)-based smart windows. The effect of dye doping on PSLC contrast was investigated. Non-dichroic dye tints the PSLC sample in both off- and on-state, which is not beneficial for increasing its off/on contrast. The sample doped with dichroic dye shows a slight color in the off-state and strong color in the on-state, resulting in an enhanced contrast, which attributed to orientation dependent absorption of dichroic dyes. Furthermore, we blended non-dichroic dye and dichroic dye who have complementary absorption together into PSLC mixture. The sample is almost colorless in the off-state due to the subtractive process, while colored in the on-state. The contrast is further enhanced. The results show that the proposed multi-dye-doped PSLC device has high visual contrast and fast response time, making it attractive for applications in light management and architectural aesthetics.

Polymer stabilised liquid crystal (PSLC) devices are widely used in various smart light modulation occasions. Their electro-optical properties can still be improved to address future challenges. It is well known that doping liquid crystal (LC) materials with nanoparticles can change the material’s electro-optical performance. In this study, silver nanoparticles (AgNPs) with size about 15–20 nm and surfactant were doped into PSLC devices. The effects of AgNPs doping on the PSLC electro-optical performances were studied. The result shows that AgNPs and surfactant doping can increase the dielectric anisotropy of LC mixture. PSLC devices with AgNPs doping have lower driving voltage and response time than un-doped PSLC devices. Therefore, doping of a specific concentration of AgNPs resulted in PSLC devices with improved electro-optical performance. Graphical abstract

In this study, we fabricated a temperature-responsive infrared reflector that adjusts to temperature changes by changing its transmittance of incident IR light. The device utilized a thermally induced change in the pitch of a cholesteric liquid crystal (CLC) to achieve near-infrared light reflection in a particular wavelength range. In addition, a polymer-stabilized cholesteric liquid crystal (PSCLC) was used as an alternative to further optimize the device performance. Polyethylene terephthalate (PET) was used as the substrate material to allow the reflector to be flexible. The light transmission performance of the reflector at different bending angles was explored, and no significant effect was found. A simulated solar device was established to study the temperature regulation effects of both CLC and PSCLC devices.

Heat sinks are widely used in electronic devices with high heat flux. The design and build of microstructures on heat sinks has shown effectiveness in improving heat dissipation efficiency. In this paper, four kinds of treatment methods were used to make different microstructures on heat sink surfaces, and thermal radiation coating also applied onto the heat sink surfaces to improve thermal radiation. The surface roughness, thermal emissivity and heat dissipation performance with and without thermal radiation coating of the heat sinks were studied. The result shows that with an increase of surface roughness, the thermal emissivity can increase up to 2.5 times. With thermal radiation coating on a surface with microstructures, the heat dissipation was further improved because the heat conduction at the coating and heat sink interface was enhanced. Therefore, surface treatment can improve the heat dissipation performance of the heat sink significantly by enhancing the thermal convection, radiation and conduction.