Lattice Hydroxyl-Assisted Platinum Single Atom Catalyst Toward Hydrogen Production From Methanol Aqueous Reforming

Area of Science:

• Catalysis
• Materials Science
• Green Chemistry

Background:

• Methanol aqueous reforming (APRM) is a promising green hydrogen production method.
• Developing efficient catalysts for APRM remains a significant challenge.
• Single-atom catalysts offer unique properties for enhanced reactivity.

Purpose of the Study:

• To design and prepare a highly efficient platinum catalyst for APRM.
• To investigate the structure-activity relationship of the catalyst.
• To elucidate the reaction mechanism for hydrogen production.

Main Methods:

• Synthesis of platinum catalyst on porous hydroxyl lanthanum oxide via glycine combustion and reduction.
• Characterization using advanced spectroscopic techniques and theoretical calculations.
• Performance evaluation through kinetic isotope analysis and in situ spectroscopy.

Main Results:

• Optimized 0.8%Pt/La catalyst with single-atom dispersed Pt on La₂(OH)_{2 x}O_{3-2 x} support achieved high performance.
• Achieved a H₂ production rate of 7672 µmol_H2 g_cat ^-1 min^-1 and ATOF of 11973 h^‒1.
• Identified Pt^{δ +} coordinated with lattice hydroxyl (OH_L) as the active site.

Conclusions:

• The Pt single-atom catalyst exhibits exceptional performance for APRM, outperforming state-of-the-art catalysts.
• The reaction mechanism involves Pt^{δ +} promoting methoxyl dehydrogenation and lattice hydroxyl participating in oxidative coupling.
• Interface sites and hydroxyl vacancies are crucial for the high catalytic activity and stability.