Highly Effective Propane Dehydrogenation Using Ga-Rh Supported Catalytically Active Liquid Metal Solutions

Area of Science:

• Catalysis
• Materials Science
• Chemical Engineering

Background:

• Rhodium is typically not considered for alkane dehydrogenation.
• Selective dehydrogenation of alkanes is crucial for producing olefins.
• Dynamic liquid metal catalysts offer unique properties.

Purpose of the Study:

• To investigate rhodium as a catalyst for selective alkane dehydrogenation.
• To explore the role of single-atom rhodium at a liquid metal interface.
• To understand the mechanism of propane dehydrogenation over Ga-Rh catalysts.

Main Methods:

• Catalytic performance testing with propane.
• In-situ spectroscopic analysis (X-ray photoelectron spectroscopy, IR-spectroscopy).
• Microscopy techniques and density-functional theory calculations.

Main Results:

• Rhodium, as single atoms on a liquid Ga-Rh alloy, exhibits high activity and selectivity for propane dehydrogenation.
• Catalyst performance dramatically increases at high Ga/Rh ratios (>80), forming liquid alloy droplets.
• Propylene is the primary product with high selectivity.

Conclusions:

• Single-atom rhodium dispersed on dynamic liquid Ga-Rh interfaces is a highly effective catalyst for selective propane dehydrogenation.
• The liquid metal alloy droplet formation is key to the enhanced catalytic activity.
• This study reveals a new class of robust and selective dehydrogenation catalysts.