Alpha-FE2O3 nanoparticles and method of making and use thereof in photodegradation of organic pollutants, as a photocatalyst and as an antibacterial composition

Patent metadata

Field	Value
Publication number	US-11235983-B2
Application number	US-201916582693-A
Country	US
Kind code	B2
Filing date	Sep 25, 2019
Priority date	Sep 25, 2019
Publication date	Feb 1, 2022
Grant date	Feb 1, 2022

Abstract

A method for producing crystalline α-Fe2O3 nanoparticles involving ultrasonic treatment of a solution of an iron (III)-containing precursor and an extract from the seeds of a plant in the family Linaceae. The method involves preparing an aqueous extract from the seeds of a plant in the family Linaceae and dropwise addition of the extract to the solution of an iron (III)-containing precursor. The method yields crystalline nanoparticles of α-Fe2O3 having a spherical morphology with a diameter of 100 nm to 300 nm, a mean surface area of 240 to 250 m2/g, and a type-II nitrogen adsorption-desorption BET isotherm with a H3 hysteresis loop. A method for the photocatalytic decomposition of organic pollutants using the nanoparticles is disclosed. An antibacterial composition containing the crystalline α-Fe2O3 nanoparticles is also disclosed.

First claim

The invention claimed is:

1. A method for producing crystalline α-Fe 2 O 3 nanoparticles, comprising:
ultrasonically treating a nanoparticle synthesis solution comprising an iron (III)-containing precursor and a Linaceae seed extract (LSE) derived from a seed from a plant in the family Linaceae to form a nanoparticle suspension; and
recovering the crystalline α-Fe 2 O 3 nanoparticles from the nanoparticle suspension,
wherein the crystalline α-Fe 2 O 3 nanoparticles have a spherical shape with a diameter from 50 to 500 nm, and an average sphericity of greater than 0.94 or a cross-section or projection with an average circularity of greater than 0.94.

2. The method of claim 1 , wherein the seed from the plant in the family Linaceae is flax seed.

3. The method of claim 1 , further comprising:
forming the LSE by:
boiling or steeping powdered seeds from the plant in the family Linaceae in water to produce a seed extract suspension; and
filtering or otherwise removing solid particles from the seed extract suspension to produce the LSE.

4. The method of claim 3 , wherein during the boiling the water has a pH of 5.5 to 8.5.

5. The method of claim 3 , wherein the LSE comprises:
at least 4 of compounds selected from the group consisting of dihydroxyacetone, 2,2′-oxybisethanol, glycerin, 2-hydroxy-gamma-butyrolactone, maltol, and 3-deoxy-d-mannoic lactone; and either cyclohexylmethyl hexadecyl ester or sucrose.

6. The method of claim 1 , wherein the iron (III)-containing precursor is iron (III) nitrate.

7. The method of claim 1 , comprising:
forming the nanoparticle synthesis solution by dropwise addition of the LSE to a solution of the iron (III)-containing precursor.

8. The method of claim 7 , wherein the iron (III)-containing precursor is present in the solution of the iron (III)-containing precursor in an amount of 0.85 to 1.15 mol Fe(III)/L.

9. The method of claim 7 , wherein the solution of the iron (III)-containing precursor comprises the iron (III)-containing precursor and water.

10. The method of claim 7 , wherein the ultrasonic treatment begins before the addition of the LSE is complete.

11. The method of claim 10 , wherein the nanoparticle synthesis solution is ultrasonically treated for 15 minutes to 4 hours.

12. The method of claim 1 , wherein the nanoparticle synthesis solution is ultrasonically treated at 45 kHz and 30 to 90 W.

13. The method of claim 1 , wherein the crystalline α-Fe 2 O 3 nanoparticles have:
a band gap of 2.10 to 2.16 eV; and
a surface area of 200 to 300 m 2 /g.

14. The method of claim 13 , wherein the crystalline α-Fe 2 O 3 nanoparticles have a Type II BET nitrogen adsorption-desorption curve with a H3 hysteresis loop and a mean pore size of 7.25 to 9.25 nm.

Assignees

• Univ Imam Abdulrahman Bin Faisal

Inventors

• Mohamed Hanan Hussein Amin

Classifications

• B01J2235/15

  X-ray diffraction · CPC title

• B01J2235/10

  Infrared [IR] · CPC title

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J2235/00

  Indexing scheme associated with group B01J35/00, related to the analysis techniques used to determine the catalysts form or properties · CPC title

• B01J35/45

  Nanoparticles · CPC title