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At least 685 records · Page 38

Coating to cool a surface by passive radiative cooling

Disclosed herein in is a radiative cooling formulation including a first component with >55% reflectance in a wavelengths range of 0.3 to 2.5 microns, a second component with a first thermal emissivity peak value greater than 0.85 at a first wavelength in a range of 8 to 13 microns (μm), and a third component to mechanically bind together a mixture of the first component and second component.

Van Overmeere, Quentin↗

Metal fluoride passivation coatings prepared by atomic layer deposition for Li-ion batteries

The fabrication of robust interfaces between transition metal oxides and non-aqueous electrolytes is one of the great challenges of lithium ion batteries. Atomic layer deposition (ALD) of aluminum tungsten fluoride (AlWxFy) improves the electrochemical stability of LiCoO 2 . AlWxFy thin films were deposited by combining trimethylaluminum and tungsten hexafluoride. in-situ quartz crystal microbalance and transmission electron microscopy studies show that the films grow in a layer-by-layer fashion and are amorphous nature. Ultrathin AlWxFy coatings (<10 Å) on LiCoO 2 significantly enhance stability relative to bare LiCoO 2 when cycled to 4.4 V. The coated LiCoO 2 exhibited superior rate capability (up to 400 mA/g) and discharge capacities at a current of 400 mA/g were 51% and 92% of the first cycle capacities for the bare and AlWxFy coated materials. These results open new possibilities for designing ultrathin and electrochemically robust coatings of metal fluorides via ALD to enhance the stability of Li-ion electrodes.

Mane, Anil U.↗

Bilateral amines for defect passivation and surface protection in perovskite solar cells

Described herein is an ink solution, comprising: i. a composition having the formula ABX 3 ; ii. a compound having the formula NH 2 —R 1 —NH 2 ; and iii. a solvent. Methods for producing polycrystalline perovskite films using the ink solutions described herein in a fast blading process and the use of the films in photoactive and photovoltaic applications are additionally described.

Huang, Jinsong↗

Spectrally selective textile for passive radiative outdoor personal cooling

A textile includes: (1) a matrix; and (2) particulate fillers dispersed within the matrix. The textile has a transmittance of infrared radiation at a wavelength of 9.5 μm of at least about 40%, and the textile has a weighted average reflectivity of radiation over a wavelength range of 0.3 μm to 2 μm of at least about 40%.

Cui, Yi↗

Scalable method of fabricating structured polymers for passive daytime radiative cooling and other applications

A switchable light transmission module is disclosed that includes a substrate having a first surface defining at least part of an enclosed volume, a porous layer disposed on the first surface and in fluid communication with the enclosed volume, and a reservoir in fluid communication with the enclosed volume. The reservoir is configured to supply a fluid to the sealed volume such that the fluid contacts the porous layer. The fluid has a refractive index that is close to the refractive index of the porous layer, has a high wettability for the porous layer, and does not dissolve the porous layer. When in a dry state, voids in the porous layer are filled with air which has a much different refractive index than the porous layer itself, resulting in a surface that is reflective and not very transmissive. During wetting of the porous layer by the fluid, however, those voids are filled with the fluid, reducing the difference in refractive index across the polymer-fluid interfaces such that light scattering is negligible and the surface becomes light permeable.

Mandal, Jyotirmoy↗

Passive and no-loss weather cap for protection of wind induced downdraft in sensitive exhaust system

The invention provides a device for removing heat from a building, the device having: a first tubular member defining a first cavity; a second tubular member defining a second cavity, whereby said second tubular member resides within the first cavity and is coaxial to the first tubular member; a double conic body coaxially residing in the first cavity and coaxially positioned with the second tubular member; and a flange dimensioned to extend over at least a portion of the periphery of the existing flue so as to aid in supporting the device on the flue.

Lisowski, Darius D.↗