Molybdenum sulfide nanosheets decorated with iron phosphide for hydrogen gas evolution

Patent metadata

Field	Value
Publication number	US-11413611-B2
Application number	US-201916707005-A
Country	US
Kind code	B2
Filing date	Dec 9, 2019
Priority date	Dec 9, 2019
Publication date	Aug 16, 2022
Grant date	Aug 16, 2022

Abstract

An electrocatalyst comprising molybdenum disulfide nanosheets with dispersed iron phosphide nanoparticles is described. The molybdenum disulfide nanosheets may have an average length in a range of 300 nm-1 μm and the iron phosphide nanoparticles may have an average diameter in a range of 5-20 nm. The electrocatalyst may have an electroactive surface area in a range of 10-50 mF·cm−2 when deposited on a working electrode for use in a hydrogen evolution reaction.

First claim

The invention claimed is:

1. An electrocatalyst, comprising:
molybdenum disulfide nanosheets having an average length in a range of 300 nm 1 μm, and
iron phosphide nanoparticles having an average diameter in a range of 5-20 nm,
wherein the iron phosphide nanoparticles are distributed on the molybdenum disulfide nanosheets with an average nearest neighbor distance of the nanoparticles between 12-20 nm.

2. The electrocatalyst of claim 1 , wherein the electrocatalyst consists essentially of Mo, S, Fe, and P.

3. The electrocatalyst of claim 1 , wherein the molybdenum disulfide nanosheets are crystalline with interplanar spacing in a range of 0.26-0.28 nm or 0.62-0.64 nm.

4. The electrocatalyst of claim 1 , wherein the molybdenum disulfide nanosheets have XRD peaks at 2(θ) Bragg angles of 33.2±1° and 59.1±1°.

5. The electrocatalyst of claim 1 , wherein the iron phosphide nanoparticles are crystalline with interplanar spacing in a range of 0.23-0.25 nm.

6. The electrocatalyst of claim 1 , wherein the iron phosphide nanoparticles have XRD peaks at 2(θ) Bragg angles of 37.2±1°, 48.3±1°, and 56.1±1°.

7. The electrocatalyst of claim 1 , which has an electroactive surface area in a range of 10-50 mF·cm −2 .

8. The electrocatalyst of claim 1 , wherein the iron phosphide nanoparticles have a Fe to P molar ratio in a range of 0.75-1.25.

9. The electrocatalyst of claim 8 , wherein the iron phosphide nanoparticles consist essentially of FeP.

10. The electrocatalyst of claim 1 , wherein a mass ratio of the iron phosphide nanoparticles to the molybdenum disulfide nanosheets is in a range of 0.60-0.95.

11. An electrocatalyst, comprising:
molybdenum disulfide nanosheets having an average length in a range of 300 nm-1 μm, and
iron phosphide nanoparticles having an average diameter in a range of 5-20 nm, and
wherein the molybdenum disulfide nanosheets have an average thickness of less than 5 nm.

12. An electrocatalyst, comprising:
molybdenum disulfide nanosheets having an average length in a range of 300 nm-1 μm, and
iron phosphide nanoparticles having an average diameter in a range of 5-20 nm, and
which has a BET surface area in a range of 10-20 m 2 /g.

13. An electrochemical cell, comprising:
a working electrode comprising the electrocatalyst of claim 1 ,
a counter electrode, and
an electrolyte solution in contact with both electrodes, the electrolyte solution comprising water and an inorganic acid.

14. The electrochemical cell of claim 13 , wherein the working electrode comprises the electrocatalyst deposited on glassy carbon, and
wherein the working electrode has an overpotential in a range of 100-140 mV/cm 2 at a current density of 10 mA/cm 2 .

15. The electrochemical cell of claim 13 , wherein the inorganic acid has a concentration in a range of 0.2-1.0 M.

16. A method for producing H 2 from an acidic electrolyte solution, the method comprising:
subjecting the electrodes of the electrochemical cell of claim 13 with a potential in a range of −1.0 to 1.0 V RHE .

17. The method of claim 16 , wherein the electrocatalyst has a turnover frequency in a range of 0.16-0.30 s −1 .

18. The method of claim 16 , wherein the electrocatalyst has a number of active sites per electrocatalyst mass in a range of 1.4 ×10 −4 to 1.4 ×10 −3 mol/g.

19. The method of claim 16 , further comprising separately collecting H 2 -enriched gas and O 2 -enriched gas.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Qamar Mohammad
• Siddiqui Mohammad Nahid
• Adam Alaaldin M Abdalla
• Suliman Munzir H

Classifications

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• C25B11/055

  characterised by the substrate or carrier material · CPC title

• B01J27/1853

  with iron, cobalt or nickel · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• C25B11/051

  Electrodes formed of electrocatalysts on a substrate or carrier · CPC title