Methods for the decoration of carbon nanoparticles with hafnium promethium oxide nanowires for energy applications

Patent metadata

Field	Value
Publication number	US-10933403-B1
Application number	US-202017004236-A
Country	US
Kind code	B1
Filing date	Aug 27, 2020
Priority date	Aug 27, 2020
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

Carbon nanoparticles are decorated with ultrafine hafnium promethium nanowires. Exemplary nanowires of hafnium promethium oxide (e.g., Hf0.7Pm0.3O2) have been fabricated. The carbon nanoparticles decorated with hafnium promethium nanowires may be used in reactions for reducing carbon dioxide to methanol, and have applications as a photocatalyst for energy applications.

First claim

The invention claimed is:

1. A carbon nanoarchitecture, photocatalyst, comprising one or more carbon nanoparticles, each of said one or more carbon nanoparticles comprising a surface decorated with ultrafine nanowires of formula Hf x Pm y O z ,
wherein,
x ranges from 0.1 to 2,
y ranges from 0.1 to 1, and
z ranges from 1 to 4.

2. The carbon nanoarchitecture photocatalyst of claim 1 , wherein the nanowires are of the formula Hf 0.7 Pm 0.3 O 2 .

3. The carbon nanoarchitecture photocatalyst of claim 1 , wherein a ratio of the one or more carbon nanoparticles to the nanowires is 1:0.75 by weight.

4. The carbon nanoarchitecture photocatalyst of claim 1 , wherein the carbon nanoarchitecture photocatalyst exhibits an optical band gap of 2.8 eV.

5. The carbon nanoarchitecture photocatalyst of claim 1 wherein the one or more carbon nanoparticles have a mean diameter in the range of 50 to 300 nm.

6. The carbon nanoarchitecture photocatalyst of claim 1 wherein z ranges from 1.8 to 2.3.

7. A method of reducing gases into renewable organic or fossil fuel, comprising exposing the gases to a carbon nanoarchitecture photocatalyst of claim 1 under ultraviolet irradiation for an exposure time sufficient to reduce CO 2 to CH 3 OH.

8. The method of claim 7 wherein the ultraviolet irradiation has a power of 10 mW/cm 2 and a A wavelength of 254 nm.

9. A method of forming a photocatalyst, comprising:
purifying carbon nanoparticles,
treating the purified carbon nanoparticles with hafnium salt to form carbon nanoparticles coated with hafnium seeds, and
treating the carbon nanoparticles coated with hafnium seeds with a hafnium salt and a promethium salt and hexamine to form one or more carbon nanoparticles comprising a surface decorated with ultrafine nanowires of formula Hf x Pm y O z ,
wherein,
x ranges from 0.1 to 2,
y ranges from 0.1 to 1, and
z ranges from 1 to 4.

10. The method of claim 9 wherein z ranges from 1.8 to 2.3.

11. The method of claim 9 wherein said hafnium salt is selected from the group consisting of hafnium chloride, hafnium nitrate, hafnium oxalate, hafnium sulfate, and hafnium acetate.

12. The method of claim 11 wherein said hafnium salt is hafnium acetate.

13. The method of claim 9 wherein said promethium salt is selected from the group consisting of promethium chloride, promethium nitrate, promethium oxalate, promethium sulfate, and promethium acetate.

14. The method of claim 13 wherein said promethium salt is promethium nitrate.

15. The method of claim 9 wherein a concentration of said promethium salt is in the range of 20 to 50% of the hafnium salt by weight.

16. The method of claim 9 wherein a concentration of said the promethium salt is 30% of the hafnium salt by weight.

17. The method of claim 7 , wherein the carbon nanoparticles have a mean diameter in the range of 50 to 300 nm.

18. The method of claim 14 , wherein the carbon nanoparticles haves a mean diameter in the range of 150 to 200 nm.

Assignees

• Univ King Abdulaziz

Inventors

• Mahmoud Waleed Elsayed
• Al-Ghamdi Ahmed Abdullah Salem
• Al-Turki Yusuf Abdulaziz

Classifications

• B01J2235/00

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

• B01J35/70

  characterised by their crystalline properties, e.g. semi-crystalline (catalysts comprising carbon B01J21/18; molecular sieves B01J29/00) · CPC title

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J35/393

  Metal or metal oxide crystallite size · CPC title

• B01J2235/15

  X-ray diffraction · CPC title