Sanitation systems and components thereof having a slippery surface
The present disclosure describes a strategy to create self-healing, slippery liquid-infused porous surfaces. Roughened (e.g., porous) surfaces can be utilized to lock in place a lubricating fluid, referred to herein as Liquid B to repel a wide range of materials, referred to herein as Object A (Solid A or Liquid A). Slippery liquid-infused porous surfaces outperforms other conventional surfaces in its capability to repel various simple and complex liquids (water, hydrocarbons, crude oil and blood), maintain low-contact-angle hysteresis (<2.5°), quickly restore liquid-repellency after physical damage (within 0.1-1 s), resist ice, microorganisms and insects adhesion, and function at high pressures (up to at least 690 atm). Some exemplary application where slippery liquid-infused porous surfaces will be useful include energy-efficient fluid handling and transportation, optical sensing, medicine, and as self-cleaning, and anti-fouling materials operating in extreme environments.
1. An article comprising a slippery surface capable of reducing adhesion of a foreign material to the article,
wherein the article is a component of a sanitation system;
wherein the article comprises:
(i) a substrate comprising a roughened surface, and
(ii) a lubricating liquid having a chemical affinity for the roughened surface, as determined by an equilibrium contact angle of less than 90°, to wet spontaneously the substrate, the lubricating liquid wetting and adhering to the roughened surface to provide a stabilized liquid overlayer on the roughened surface, without dewetting from the substrate, to form the slippery surface; and
wherein the foreign material comprises waste water, dirt, a fecal matter, urine, blood, a bacterium, a virus, a fungus, a bodily fluid, a tissue, or a combination thereof.
2. The article according to claim 1 , wherein the article is a toilet or a sink.
3. The article according to claim 1 , wherein the chemical affinity of the lubricating liquid for the roughened surface is determined by an equilibrium contact angle of less than 90°.
4. The article according to claim 1 , wherein the roughened surface comprises one or more functional groups chemically attached to the roughened surface; and
wherein the lubricating liquid has a chemical affinity for the one or more functional groups.
5. The article according to claim 4 , wherein the one or more functional groups are selected from the group consisting of a fluorinated carboxylic acid, a fluorinated phosphonic acid, a fluorinated sulfonic acid, a fluorinated silane, an end-functionalized fluorinated polymer, a straight-chain or branched-chain fluorocarbon, a straight-chain or branched-chain hydrocarbon, and a combination thereof.
6. The article according to claim 1 , wherein the roughened surface has a predetermined roughness; and
wherein the predetermined roughness is effective to immobilize the lubricating liquid on the roughened surface.
7. The article according to claim 1 , wherein the substrate comprises a plurality of raised structures; and
wherein the plurality of raised structures have feature sizes ranging from about 10 nm to about 100 μm, and are substantially free of three-dimensionally interconnected pores.
8. The article according to claim 1 , wherein the substrate comprises a glass, a ceramic, a plastic, a rubber, a metal, or a combination thereof.
9. The article according to claim 1 , wherein the lubricating liquid is selected from the group consisting of fully or partially fluorinated carboxylic acids, fully or partially fluorinated phosphonic acids, fully or partially fluorinated sulfonic acids, fully or partially fluorinated silanes, fully or partially fluorinated hydrocarbons, fully or partially fluorinated organosilicone compounds, fully or partially fluorinated alkylamines, fully or partially fluorinated alkylsulfides, fully or partially fluorinated alkylsulfoxides, fully or partially fluorinated alkylethers, fully or partially fluorinated cycloethers, fully or partially fluorinated polyethers, fully or partially fluorinated alkylphosphines, fully or partially fluorinated phosphineoxides, liquid hydrocarbons, oils, and mixtures thereof.
10. The article according to claim 1 , wherein the lubricating liquid comprises an oil.
11. The article according to claim 1 , wherein the article further comprises a reservoir containing additional lubricating liquid, and
wherein the additional lubricating liquid replenishes the lubricating liquid on the roughened surface.
12. The article according to claim 11 , wherein the article is a toilet; and
wherein the lubricating liquid is flushed into the toilet bowl to replenish the lubricating liquid on the roughened surface.
13. The article according to claim 1 , wherein the article is a toilet;
wherein the substrate comprises a ceramic;
wherein the roughened surface comprises one or more functional groups chemically attached to the roughened surface;
wherein the lubricating liquid has a chemical affinity for the one or more functional groups; and
wherein the foreign material comprises a fecal matter, a bodily fluid, or a combination thereof.