Hyper-cross-linked polymer supported rhodium: an effective catalyst for hydrogen evolution from ammonia borane

Area of Science:

• Materials Science
• Catalysis
• Nanotechnology

Background:

• Metal nanoparticles (NPs) are crucial for hydrogen evolution in ammonia-borane (AB) hydrolysis due to their high surface area and catalytic activity.
• Developing stable and highly active catalysts is essential for efficient hydrogen generation.

Purpose of the Study:

• To synthesize and characterize a novel catalyst support for stabilizing rhodium nanoparticles (Rh NPs).
• To evaluate the catalytic performance of the prepared Rh NPs on the support for hydrogen generation from AB hydrolysis.

Main Methods:

• Synthesis of a hyper-cross-linked polymer (HCP-PPh3) via Friedel-Crafts reaction.
• Immobilization of Rh NPs onto the HCP-PPh3 support, achieving uniform dispersion and an average particle size of 2.1 nm.
• Testing the catalytic activity of HCP-PPh3-Rh for AB hydrolysis under mild conditions.

Main Results:

• Characterization confirmed uniform dispersion of small Rh NPs on the HCP-PPh3 support.
• The HCP-PPh3-Rh catalyst exhibited a high turnover frequency of 481 mol H2 (molRh min)-1 for AB hydrolysis.
• The catalyst demonstrated excellent performance attributed to small NP size and strong metal-support interaction.

Conclusions:

• The developed HCP-PPh3 support effectively stabilizes Rh NPs for enhanced catalytic activity.
• This strategy offers a promising route for preparing highly active, supported metal nanoparticles for hydrogen generation via AB hydrolysis.
• The catalyst's performance highlights its potential for efficient and sustainable hydrogen production.