Vanadium dioxide/titanium nitride (VO /TiN) smart coatings are prepared by hybridizing thermochromic VO with plasmonic TiN nanoparticles. The VO /TiN coatings can control infrared (IR) radiation dynamically in accordance with the ambient temperature and illumination intensity. It blocks IR light under strong illumination at 28 °C but is IR transparent under weak irradiation conditions or at a low temperature of 20 °C. The VO /TiN coatings exhibit a good integral visible transmittance of up to 51% and excellent IR switching efficiency of 48% at 2000 nm. These unique advantages make VO /TiN promising as smart energy-saving windows.

The room-temperature ionic liquid 1-allyl-3-methyl-imidazolium chloride [amim][CI] was synthesized. The conductivities and viscosities of [amim][CI] + water and + ethanol binary mixtures were determined in the temperature range from 293.15 K to 333.15 K, and the mole fraction of the solvents in the mixtures was in the range of 0 to 0.80 for water and 0 to 0.55 for ethanol. The conductivities of the mixtures increased with increasing concentration of the solvents and temperature in the solvent concentration range studied. The viscosities of the mixtures decreased with increasing temperature.

Hydrogen (H2) has been considered as one of the cleanest renewable energy sources. However, it is still challenging in using H2, due to its hazardous for flammable and explosive properties...

Although high-energy facets on metal oxides are usually active and preferred for gas sensing, it is difficult to expose them according to thermodynamics. In this work, nanocomposites of SnO2 and graphene are prepared by a hydrothermal method. The SnO2 nanoparticles change from a lance shape to an octahedral shape as the concentration of HCl in the solution is increased gradually from 6.5 to 10 vol %. However, the SnO2 nanoparticles have an elongated octahedral shape if the concentration of HCl is increased further. The octahedral SnO2 nanoparticles are mainly surrounded by high-surface-energy {221} facets, thus facilitating gas sensing. First-principles calculation shows that the surface energy and adsorption energy of the {221} facets are larger than those of the stable {110} facets, and so, the gas adsorption capacity on the {221} facets is better. Furthermore, because the Fermi level of the SnO2{221} facet is higher than that of graphene, the electrons are transferred from SnO2 nanoparticles to graphene sheets, enabling effective electron exchange between the composite and external NO2 gas. The excellent gas-sensing properties of the octahedral SnO2/graphene composites are ascribed to the high-surface-energy {221} facets exposed.

Nanoscale tungsten oxides (WO3/W18O49) have been studied quite hot because of their impeccable performance in different fields, such as multi-step responses to one stimulus or selectively responding to a stimulus...

Thermochromic smart windows can provide innovative energy savings via intelligently modulating the transmittance of indoor solar radiation to reduce the energy consumption of air conditioning in buildings. Vanadium dioxide (VO2) has desirable thermochromic properties and great prospects in smart windows. Herein, 3D ordered macroporous (3DOM) VO2 films are prepared via a sacrificial colloid template method. The as‐fabricated 3DOM VO2 films exhibit a pure monoclinic phase with a uniform layout, controllable thickness and domain sizes, and excellent optical properties. Compared to a nontemplated film, the 3DOM structured VO2 exhibits improved thermochromic performance with a high solar modulation ability (ΔTsol) of 10.8% and an ultrahigh visible transmittance (Tvis) of 71.1%. In the near‐infrared region, a large contrast transmittance of 59.5% at 2500 nm is obtained for the 3DOM VO2 film. Such excellent optical properties arising from the 3DOM structure are also demonstrated by finite element analysis. This work offers a promising way to manipulate the optical properties of a VO2 thermochromic film via structural engineering for the deployment of smart windows.

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