Apparatus and method for nanoporous inorganic membranes and films, methods of making and usage thereof

Patent metadata

Field	Value
Publication number	US-9873090-B2
Application number	US-201313968833-A
Country	US
Kind code	B2
Filing date	Aug 16, 2013
Priority date	Jun 17, 2009
Publication date	Jan 23, 2018
Grant date	Jan 23, 2018

Abstract

A method for fabricating isolated pores in an inorganic membrane includes the steps of patterning the inorganic membrane to selectively expose a portion of the membrane, forming a plurality of tracks of material damage in the exposed portion of the inorganic membrane by irradiation with energetic ions, and chemically etching the track damaged material to define the pores through the inorganic membrane with a predetermined geometrically defined cross sectional shape and with a controlled diameter range from less than 1 nanometer and up to micrometer scale.

First claim

We claim:

1. A method for manufacturing a desalination membrane, the method comprising:
obtaining a film;
forming a plurality of conically-shaped nanopores in the film, the conically-shaped nanopores comprising internal surfaces;
chemically modifying the internal surfaces of the nanopores with amine-containing groups by silanization;
wherein at least a portion of the internal surfaces of the nanopores comprise amine-containing groups;
wherein the amine-containing groups are positively charged at pH<9;
wherein the membrane resists the passage of ions based on electrostatic interactions with the conical nanopores.

2. The method of claim 1 , wherein the internal surfaces of the nanopores are chemically modified with the amine-containing groups.

3. The method of claim 1 , wherein the internal surfaces of the nanopores comprise negatively charged species, wherein at least a portion of the negatively charged species are chemically modified to provide the amine-containing groups.

4. The method of claim 1 , further comprising chemically etching the film to provide the conically-shaped nanopores.

5. The method of claim 1 , further comprising patterning the film to selectively expose at least a portion of the film to radiation.

6. The method of claim 1 , further comprising irradiating the film with energetic ions to form a plurality of tracks of material damage.

7. The method of claim 6 , wherein the energetic ions have an atomic number of 8 or greater.

8. The method of claim 6 , wherein the energetic ions have an atomic number of 18 or greater.

9. The method of claim 5 , wherein the patterning of the film is performed using lithography.

10. The method of claim 1 , wherein the film is an amorphous inorganic material.

11. The method of claim 1 , wherein a nanopore density of the film is between 10 8 pores per cm 2 and 10 9 pores per cm 2 .

12. The method of claim 1 , wherein the membrane rejects the passage of molecules based on size.

13. The method of claim 4 , wherein chemically etching of the film is performed using H 3 PO 4 or HF.

Assignees

• Univ California

Inventors

• Siwy Zuzanna S
• Vlassiouk Ivan V
• Apel Pavel Yu
• Dmitriev Sergey N

Classifications

• B01D61/18

  Apparatus therefor · CPC title

• B01D67/0062 Primary

  by micromachining techniques, e.g. using masking and etching steps, photolithography · CPC title

• B01D61/14

  Ultrafiltration; Microfiltration · CPC title

• B01D71/02

  Inorganic material · CPC title

• B01D71/0215

  Silicon carbide; Silicon nitride; Silicon oxycarbide · CPC title