Polymer electrolyte membrane (pem) electrolytic cells using zeolite-templated carbon (ztc) as electrocatalyst

Patent metadata

Field	Value
Publication number	US-2023023125-A1
Application number	US-202117450416-A
Country	US
Kind code	A1
Filing date	Oct 8, 2021
Priority date	Jul 14, 2021
Publication date	Jan 26, 2023
Grant date	—

Abstract

A polymer electrolyte membrane (PEM) electrolytic cell assembly, and a method for making the assembly, are provided. An exemplary method includes forming a functionalized zeolite templated carbon (ZTC), including forming a CaX zeolite, depositing carbon in the CaX zeolite using a chemical vapor deposition (CVD) process to form a carbon/zeolite composite, treating the carbon/zeolite composite with a solution including hydrofluoric acid to form a ZTC, and treating the ZTC to add catalyst sites, forming the functionalized ZTC. The method further includes incorporating the functionalized ZTC into electrodes, forming a membrane electrode assembly (MEA), and forming the PEM electrolytic cell assembly. The method further includes coupling the PEM electrolytic cell assembly to a heat source.

First claim

What is claimed is:

1 . A method for making a polymer electrolyte membrane (PEM) electrolytic cell assembly, comprising:
forming a functionalized zeolite templated carbon (ZTC), comprising:
forming a CaX zeolite;
depositing carbon in the CaX zeolite using a chemical vapor deposition (CVD) process to form a carbon/zeolite composite;
treating the carbon/zeolite composite with a solution comprising hydrofluoric acid to form a ZTC; and
treating the ZTC to add catalyst sites, forming the functionalized ZTC; and incorporating the functionalized ZTC into electrodes; forming a membrane electrode assembly; forming the PEM electrolytic cell assembly; and coupling the PEM electrolytic cell assembly to a heat source.

2 . The method of claim 1 , wherein the CaX zeolite is formed by ion exchanging a NaX zeolite with calcium ions.

3 . The method of claim 1 , wherein the CVD process uses propylene, ethanol, or acetylene, or any combinations thereof, as an organic precursor gas.

4 . The method of claim 1 , wherein the CVD process uses acetylene as an organic precursor gas.

5 . The method of claim 4 , wherein the acetylene is added as a 2 vol. % solution in helium.

6 . The method of claim 1 , wherein the CVD process is performed at a temperature of between 823 K and 1123 K.

7 . The method of claim 1 , wherein the CVD process comprises:
depositing carbon in a matrix of the CaX zeolite at a first temperature using a gas stream comprising acetylene; switching the gas stream to a helium stream; and increasing the temperature to a second temperature.

8 . The method of claim 7 , wherein the first temperature is less than 875 K.

9 . The method of claim 7 , wherein the first temperature is about 823 K.

10 . The method of claim 7 , wherein the second temperature is greater than 1120 K.

11 . The method of claim 7 , wherein the second temperature is about 1123 K.

12 . The method of claim 7 , comprising repeating the CVD process by cooling back to the first temperature;
switching the gas stream back to the gas stream comprising acetylene; depositing carbon in the matrix of the CaX zeolite at the first temperature; switching the gas stream to the helium stream; and increasing the temperature to the second temperature.

13 . The method of claim 1 , comprising forming the functionalized ZTC using an incipient wetness technique.

14 . The method of claim 1 , comprising:
dissolving an active metal precursor to form an aqueous solution; adding an amount of the aqueous solution to the ZTC corresponding to a pore volume of the ZTC forming a metal/ZTC composite; drying the metal/ZTC composite; and sintering the metal/ZTC composite to form the functionalized ZTC.

15 . The method of claim 1 , comprising adhering the functionalized ZTC to a surface of an anode, a cathode, or both, using an ion conductive adhesive.

16 . The method of claim 1 , comprising incorporating the functionalized ZTC into an anode, a cathode, or both by sputtering.

17 . The method of claim 1 , comprising forming the MEA by pressing an anode, a PEM, and a cathode together in a hot press, wherein the surface of the anode, the cathode, or both, that faces the PEM is coated with the functionalized ZTC.

18 . The method of claim 1 , comprising forming the PEM electrolytic cell assembly by mounting the MEA in a housing with an inlet for steam.

19 . A polymer electrolyte membrane (PEM) electrolytic cell, comprising:
a membrane electrode assembly (MEA), comprising:
an anode;
a polymer electrolyte membrane (PEM); and
a cathode, wherein the anode, the cathode, or both comprises functionalized zeolite templated carbon (ZTC);
a housing comprising an inlet for water and an outlet for hydrogen; a power line coupled to the cathode to provide current to the PEM electrolytic cell from an external power supply; and a return line from the external device coupled to the anode.

20 . The PEM electrolytic cell of claim 19 , comprising a layer of functionalized zeolite template carbon disposed at the interface between the anode and the PEM, the interface between the cathode and the PEM, or both.

21 . The PEM electrolytic cell of claim 19 , wherein the functionalized ZTC is formed by a method comprising:
forming a CaX zeolite; depositing carbon in the CaX zeolite using a chemical vapor deposition (CVD) process to form a carbon/zeolite composite; treating the carbon/zeolite composite with a solution comprising hydrofluoric acid to form a ZTC; and treating the ZTC to add catalyst sites, forming the functionalized ZTC.

Assignees

• Saudi Arabian Oil Co

Inventors

• Hammad Ahmad D
• Amr Issam T
• Wang Yuguo
• Lithoxoos Georgios
• Othman Rashid M

Classifications

• C25B9/67

  Heating or cooling means · CPC title

• C25B9/65

  Means for supplying current; Electrode connections; Electric inter-cell connections · CPC title

• C25B9/23 Primary

  comprising ion-exchange membranes in or on which electrode material is embedded · CPC title

• C25B1/04

  by electrolysis of water · CPC title

• C25B9/63

  Holders for electrodes; Positioning of the electrodes · CPC title