US 11,958,006 B2Granted

Laser-induced graphene filters and methods of making and using same

AssigneesWilliam Marsh Rice University, B.G. Negev Technologies and Applications Ltd., At Ben-Gurion University

InventorsJames M. Tour, Michael G. Stanford, John Li, Yieu Chyan, Christopher John Arnusch, Steven E. Presutti

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Abstract

Virus and microbe-killing, self-sterilizing resistive heated air filters and methods of making and using same methods. The air filter is includes laser-induced graphene (LIG), a porous conductive graphene foam formed through photothermal conversion of a polyimide film (or another source or source of polymer or other LIG precursor material) by a laser source. The LIG in the air filter can capture particulates and bacteria. The bacteria cannot proliferate even when submerged in culture medium. Through a periodic Joule-heating mechanism, the filter easily reaches greater than 300° C. This destroys any microorganisms including bacteria, along with molecules that can cause adverse biological reactions and diseases such as viruses, pyrogens, allergens, exotoxins, endotoxins, teichoic acids, mycotoxins, nucleic acids, and prions.

Claims30

Dependent claims

A method of making a filter comprising LIG, wherein the method comprises the steps of:

(a) exposing a first side of a sheet comprising a LIG precursor material to a first laser source, wherein
(i) the exposing on the first side results in formation of LIG on the first side of the sheet,
(ii) the LIG is derived from the LIG precursor material, and
(iii) some of the LIG precursor material on the first side of the sheet is not exposed to the first laser source such that it remains LIG precursor material on the first side of the sheet;
and
(b) treating the second side of the sheet, wherein
(i) the second side of the sheet is on the opposite side of the first side of the sheet,
(ii) the step of treating the second side comprises exposing the second side of the sheet to a second laser source to form LIG on the second side of the sheet,
(iii) the second laser source is (A) the first laser source or (B) a different laser source than the first laser source,
(iv) the LIG on the first side of the sheet and the LIG on the second side of the sheet are adjacent and provide a porosity to the sheet such that the sheet is a LIG filter configured to allow a flow of air through the LIG from the first side of the sheet to the LIG on the second side of the sheet,
(v) the LIG precursor material not formed into LIG by the exposing of the first laser source on the first side is a support of the LIG formed on the first side, and
(vi) the LIG precursor material not formed into LIG by the exposing of the second laser source on the second side is a support of the LIG formed on the second side.

9 more elements

Dependencies are inferred from the claim text.

Facts

Application: 16/969,131Filed 10 Aug 2020 · us provisional application
Priority: 9 Aug 2019
Published: US 2023/0173419 A18 Jun 2023
Granted: 16 Apr 2024
Term ends: Not estimatedThe source records don’t support an estimate.

Classification14 codes

B01D 39/2055
Of inorganic material, e.g. asbestos paper, metallic filtering material of non-woven wires: carbonaceous material
B01D 39/2065
Carbonaceous material: the material being fibrous
B01D 46/0001
Filters or filtering processes specially modified for separating dispersed particles from gases or vapours: making filtering elements
B01D 46/48
Auxiliary equipment or operation thereof: removing dust other than cleaning filters , e.g. by using collecting trays