US-12616961-B1 - Method of producing hydrogen gas

Abstract

A method of producing hydrogen gas that includes contacting a catalytic MnO 2 /MgO/CuO/g-C 3 N 4 nanocomposite with a solution including water and a borohydride source. The catalytic MnO 2 /MgO/CuO/g-C 3 N 4 nanocomposite includes 5 to 15 wt. % MgO nanoparticles, 5 to 15 wt. % MnO 2 nanoparticles, 15 to 25 wt. % CuO nanoparticles, and 55 to 65 wt. % g-C 3 N 4 nanosheets. The MgO nanoparticles, MnO 2 nanoparticles, and CuO nanoparticles are disposed on the g-C 3 N 4 nanosheets.

Inventors

• Mohamed Nady Abd El-Hameed Ibrahim
• Laila Saad Saied Alqarni

Assignees

• IMAM MOHAMMAD IBN SAUD ISLAMIC UNIVERSITY

Dates

Publication Date

20260505

Application Date

20250717

Claims (16)

1. 1 . A method of forming hydrogen gas, the method comprising reacting a borohydride with water in the presence of a MnO 2 /MgO/CuO/g-C 3 N 4 nanocomposite as a catalyst to form hydrogen gas, wherein the MnO 2 /MgO/CuO/g-C 3 N 4 nanocomposite comprises 5 to 15 wt. % MgO nanoparticles; 5 to 15 wt. % MnO 2 nanoparticles; 15 to 25 wt. % CuO nanoparticles; and 55 to 65 wt. % g-C 3 N 4 nanosheets, and wherein the MgO nanoparticles, MnO 2 nanoparticles, and CuO nanoparticles are disposed on the g-C 3 N 4 nanosheets.
2. 2 . The method of claim 1 , wherein the MgO nanoparticles have a mean particle size of 10 to 1000 nm, the MnO 2 nanoparticles have a mean particle size of 10 to 1000 nm, and the CuO nanoparticles have a mean particle size of 10 to 1000 nm.
3. 3 . The method of claim 1 , wherein the g-C 3 N 4 nanosheets have a mean nanosheet size of 50 to 5000 nm and a mean nanosheet thickness of 0.5 to 50 nm.
4. 4 . The method of claim 1 , further comprising: forming the catalytic MnO 2 /MgO/CuO/g-C 3 N 4 nanocomposite by: ultrasonically treating a mixture of MgO nanoparticles; CuO nanoparticles; and g-C 3 N 4 nanosheets to form a nanoparticle mixture; adding the MnO 2 nanoparticles to the nanoparticle mixture to form a nanocomposite precursor; and heating the nanocomposite precursor to 250 to 450° C. to form the catalytic MnO 2 /MgO/CuO/g-C 3 N 4 nanocomposite.
5. 5 . The method of claim 4 , further comprising heating a first solution comprising a magnesium ion source and a first hydroxide base to 50 to 100° C. to form a magnesium hydroxide intermediate; and calcining the magnesium hydroxide intermediate at 300 to 500° C. to form the MgO nanoparticles.
6. 6 . The method of claim 5 , wherein the first hydroxide base is NaOH.
7. 7 . The method of claim 5 , wherein the magnesium ion source is magnesium nitrate.
8. 8 . The method of claim 5 , wherein the first solution has a molar ratio of magnesium ion source to first hydroxide base of 1:8 to 1:1.
9. 9 . The method of claim 4 , further comprising gelling glycerol and potassium permanganate to form a gel; aging the gel for 12 to 48 hours to form an aged gel; washing the aged gel to form a manganese precursor; and calcining the manganese precursor at 600 to 800° C. to form the MnO 2 nanoparticles.
10. 10 . The method of claim 9 , wherein the gel has a molar ratio of potassium permanganate to glycerol of 1:10 to 1:2.
11. 11 . The method of claim 4 , further comprising forming the CuO nanoparticles by mixing a copper ion source and a second hydroxide base to form a copper intermediate; and calcining the copper intermediate at 400 to 600° C. to form the CuO nanoparticles.
12. 12 . The method of claim 11 , wherein the second hydroxide base is NaOH.
13. 13 . The method of claim 11 , wherein the copper ion source is copper chloride.
14. 14 . The method of claim 4 , further comprising forming the g-C 3 N 4 nanosheets by heating urea to 450 to 650° C. to form the g-C 3 N 4 nanosheets.
15. 15 . The method of claim 1 , wherein the borohydride is sodium borohydride.
16. 16 . The method of claim 1 , wherein the method has a hydrogen generation rate of 850 to 1150 mL per minute per gram of sodium borohydride at 40° C.

Description

BACKGROUND Technical Field The present disclosure is directed towards a method of producing hydrogen gas using a particulate crystalline nanocomposite catalyst. Description of Related Art The “background” description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present invention. The increasing global industrialization and population growth have resulted in a heightened demand for sustainable and reliable energy sources capable of addressing the growing need for electricity. The depletion of non-renewable energy resources and escalating environmental concerns have prompted the urgent need for a transition to alternative, renewable energy solutions. While solar energy offers an abundant and cost-effective option, challenges remain in energy storage due to reliance on expensive and disposable batteries, which require frequent replacement. Additionally, the combustion of fossil fuels continues to release harmful emissions, including carbon dioxide, nitrogen oxides, sulfur oxides, and particulate matter, contributing to various environmental pollution problems. In response to these challenges, there exists a growing need for clean, renewable energy sources and storage forms. Hydrogen (H2) has emerged as a promising energy carrier due to its high energy density, non-toxicity, and environmental benefits. Specifically, hydrogen's energy density is significantly higher than that of liquid hydrocarbons, positioning it as an attractive solution for energy storage and production. However, challenges related to hydrogen production, storage, and transportation persist, including high costs associated with compression, liquefaction, and the potential for gas leakage under high pressure. Metal hydrides have been proposed as a means of storing hydrogen, but their practical application is limited by the need for elevated temperatures and sensitivity to air, which restrict their widespread use. Borohydrides, particularly sodium borohydride (NaBH4), have been identified as a superior alternative for hydrogen storage due to their high hydrogen storage capacity, thermal and chemical stability, and environmentally friendly byproducts. Sodium borohydride is a stable, lightweight material capable of efficiently releasing hydrogen, making it a viable candidate for on-demand hydrogen production. While metal borohydrides have excellent properties for storging hydrogen, they suffer from disadvantages is retrieving the stored hydrogen in usable form. Typically, the rates of hydrogen production from metal borohydrides are sluggish or inefficient. To improve production rates, methods primarily rely on costly and rare noble metal catalysts, which hinder the scalability and practicality of such processes due to their high cost, low abundance, and possible incompatibility with other processes or subsequent use. As such, there is a growing interest in developing catalysts based on more abundant and cost-effective transition metals. Accordingly, one objective of the present disclosure is to provide methods and compositions that enhance the performance, reduce costs, and offer greater flexibility in producing hydrogen, thereby overcoming the aforementioned drawbacks and limitations associated with known materials and methods for hydrogen production from borohydrides. SUMMARY According to a first aspect, the present disclosure relates to a method of producing hydrogen gas. In some embodiments, the method includes contacting a catalytic MnO2/MgO/CuO/g-C3N4 nanocomposite with a solution including water and a borohydride source. In some embodiments, the catalytic MnO2/MgO/CuO/g-C3N4 nanocomposite includes 5 to 15 wt. % MgO nanoparticles, 5 to 15 wt. % MnO2 nanoparticles, 15 to 25 wt. % CuO nanoparticles, and 55 to 65 wt. % g-C3N4 nanosheets. In some embodiments, the MgO nanoparticles, MnO2 nanoparticles, and CuO nanoparticles are disposed on the g-C3N4 nanosheets. In some embodiments, the MgO nanoparticles have a mean particle size of 10 to 1000 nanometers (nm). The MnO2 nanoparticles have a mean particle size of 10 to 1000 nm. The CuO nanoparticles have a mean particle size of 10 to 1000 nm. In some embodiments, the g-C3N4 nanosheets have a mean nanosheet size of 50 to 5000 nm and a mean nanosheet thickness of 0.5 to 50 nm. In some embodiments, the method includes forming the catalytic MnO2/MgO/CuO/g-C3N4 nanocomposite. In some embodiments, the method includes ultrasonically treating a mixture of the MgO nanoparticles, CuO nanoparticles, and g-C3N4 nanosheets to form a nanoparticle mixture. In some embodiments, the method includes adding the MnO2 nanoparticles to the nanoparticle mixture to form a nanocomposite precursor. In some embo