Crystalline α-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-11739003-B2
Application number	US-202117543899-A
Country	US
Kind code	B2
Filing date	Dec 7, 2021
Priority date	Sep 25, 2019
Publication date	Aug 29, 2023
Grant date	Aug 29, 2023

Abstract

Crystalline α-Fe 2 O 3 nanoparticles prepared by 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 crystalline α-Fe 2 O 3 nanoparticles have a spherical morphology with a diameter of 100 nm to 300 nm, a mean surface area of 240 to 260 m 2 /g, and a type-II nitrogen adsorption-desorption BET isotherm with a H3 hysteresis loop. The crystalline α-Fe 2 O 3 nanoparticles have a band gap of 2.10 to 2.16 eV and a mean pore size of 7.25 to 9.25 nm. A method for the photocatalytic decomposition of organic pollutants using the crystalline α-Fe 2 O 3 nanoparticles. An antibacterial composition containing the crystalline α-Fe 2 O 3 nanoparticles.

First claim

The invention claimed is:

1. Crystalline nanoparticles of α-Fe 2 O 3 having a spherical shape with a diameter from 50 to 500 nm, wherein the crystalline nanoparticles of α-Fe 2 O 3 have:
an average sphericity of greater than 0.94 or a cross-section or projection with an average circularity of greater than 0.94;
a band gap of 2.10 to 2.16 eV;
a surface area of 240 to 260 m 2 /g;
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.

2. The crystalline nanoparticles of claim 1 , wherein the nanoparticles are monodisperse, having a coefficient of variation defined as the ratio of a standard deviation of diameters to an average diameter of less than 0.15.

3. A method for the photodegradation of an organic pollutant comprising:
contacting the crystalline nanoparticles of α-Fe 2 O 3 of claim 1 and at least one organic pollutant selected from the group consisting of a dye, a phenol, a polycyclic aromatic hydrocarbon, an herbicide, and a pesticide, in a solvent to form a solution; and
irradiating the solution with a visible light source to photodegrade the organic pollutant.

4. The method of claim 3 , wherein the nanoparticles are present in the solution in an amount of 0.5 to 1.5 g/L.

5. A photocatalyst, comprising:
the crystalline nanoparticles of claim 1 , and
nanoparticles of a non-iron metal oxide.

6. An antibacterial composition, comprising:
the crystalline nanoparticles of claim 1 having a MIC value against Staphylococcus aureus and/or E. coli of 1 to 1000 ppm.

7. The crystalline nanoparticles of claim 1 prepared by a method comprising:
ultrasonically treating a nanoparticle synthesis solution comprising an iron (III)-containing precursor and a Linaceae seed extract 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.

8. The crystalline nanoparticles of claim 7 wherein the method of making the crystalline nanoparticles further comprises:
forming the Linaceae seed extract 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 Linaceae seed extract.

9. The crystalline nanoparticles of claim 7 wherein the Linaceae seed extract used to make the crystalline nanoparticles 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.

10. The crystalline nanoparticles of claim 7 , wherein the iron (III)-containing precursor used to make the crystalline nanoparticles is iron (III) nitrate.

11. The crystalline nanoparticles of claim 7 , wherein the method used to make the crystalline nanoparticles includes ultrasonically treating the nanoparticle synthesis solution at 45 kHz and 30 to 90 W.

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