2results about How to "Guaranteed wettability" patented technology

This application relates to the field of proton exchange membrane fuel cell technology, and provides a gas diffusion layer, its preparation method, and its application. The gas diffusion layer includes a substrate layer and a microporous layer disposed on one side of the substrate layer. The substrate layer has stacked carbon fibers with voids between them. The microporous layer permeates into the substrate layer, forming overlapping portions, and partially permeates into the voids formed by the carbon fibers in the substrate layer. The microporous layer has a fluorine content of 12wt% to 25wt%, and the water contact angle difference between the microporous layer and the substrate layer is Δ, where Δ satisfies 0°≤Δ≤5°. This gas diffusion layer not only has good water drainage and permeability, but also, through the stacked arrangement of the substrate layer and the microporous layer, which gives the substrate layer and the microporous layer similar water properties, effectively reduces the condensation of water vapor in the permeate gas within the gas diffusion layer, increases the humidity of the permeate gas, and thus effectively maintains the wettability of the proton exchange membrane fuel cell.

The application discloses a gradient-wetting Janus ceramic membrane and a preparation method and application thereof. In the preparation, a porous ceramic substrate with hydrophilic double main surfaces is taken, one main surface of the porous ceramic substrate is treated with a solution containing a hydrophobic modifier (without contacting the other main surface), a photocatalyst is loaded on the treated surface, and at least three continuous sub-regions are divided, different-length activation radiation is applied to each sub-region to form a gradient-wetting region with a water contact angle gradually changing along a preset direction, and finally, the photocatalyst is removed and dried. The obtained membrane has an asymmetric structure, one side has precisely regulated gradient-wetting, and the other side remains hydrophilic. When the membrane is applied to scenes such as carbon capture and regeneration of waste heat recovery of gas, the surface wettability of the membrane can be accurately matched with a local thermodynamic and concentration environment along the way, heat and mass transfer can be strengthened, surface self-cleaning can be realized, the performance of the membrane is superior to that of a traditional membrane, and the energy-saving and consumption-reducing potential is great.