Molybdenum sulfide nanosheets decorated with iron phosphide for hydrogen gas evolution

Patent metadata

Field	Value
Publication number	US-2021170384-A1
Application number	US-201916707005-A
Country	US
Kind code	A1
Filing date	Dec 9, 2019
Priority date	Dec 9, 2019
Publication date	Jun 10, 2021
Grant date	—

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

1 . An electrocatalyst, comprising:
molybdenum disulfide nanosheets having an average length in a range of 300 nm-1 pm, and iron phosphide nanoparticles having an average diameter in a range of 5-20 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 , 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.

8 . The electrocatalyst of claim 1 , wherein the molybdenum disulfide nanosheets have an average thickness of less than 5 nm.

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

10 . The electrocatalyst of claim 1 , which has a BET surface area in a range of 10-20 m 2 /g.

11 . 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.

12 . The electrocatalyst of claim 11 , wherein the iron phosphide nanoparticles consist essentially of FeP.

13 . 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.

14 . 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.

15 . The electrochemical cell of claim 14 , 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 .

16 . The electrochemical cell of claim 14 , wherein the inorganic acid has a concentration in a range of 0.2-1.0 M.

17 . A method for producing H 2 from an acidic electrolyte solution, the method comprising:
subjecting the electrodes of the electrochemical cell of claim 14 with a potential in a range of −1.0 to 1.0 V RHE .

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

19 . The method of claim 17 , 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.

20 . The method of claim 17 , 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

• B82Y30/00

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

• C25B11/091

  consisting of at least one catalytic element and at least one catalytic compound; consisting of two or more catalytic elements or catalytic compounds · CPC title

• Y02E60/36

  Hydrogen production from non-carbon containing sources, e.g. by water electrolysis · CPC title

• C25B1/04 Primary

  by electrolysis of water · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title