SUMMARY
UCLA researchers in the Department of Chemistry and Biochemistry have developed an electrocatalytic system for CH4 functionalization using silver (AgII) as a metalloradical mediator that works at low temperatures with minimal infrastructure.
BACKGROUND
Methane (CH4) release occurs in a wide array of industrial processes, including natural gas extraction. Typically, these processes release excess CH4 into the atmosphere contributing to climate change. CH4 functionalization is essential for multiple chemical processes and offers a solution for utilizing CH4 to prevent its release into the atmosphere. Ambient methane (CH4) functionalization offers a route of chemical synthesis that mitigates the emission of CH4 from the environment that comes from natural gas. The primary obstacle encountered when attempting CH4 functionalization is the high C-H bond dissociation energy, leading to CH4 stability at ambient conditions. The most common homogeneous catalysts contain metals such as gold, palladium, and mercury. Nevertheless, these metals require strong acids and may lead to the formation of undesirable products. Metals such as manganese and cobalt have been used to activate the C-H bond of CH4. However, these active metal catalysts require elevated temperatures (50 °C – 220 °C). Therefore, there is a need to explore other type of metal catalysts that may aid on the activation of C-H bonds in CH4 using mild conditions.
INNOVATION
UCLA researchers in the Department of Chemistry and Biochemistry have developed an electrocatalytic system for CH4 functionalization using silver (AgII) as a metalloradical mediator. The method showed radical conversion of CH4 to CH3• with a high kinetic rate constant. The developed electrocatalytic system haa high reaction selectivity at low temperatures and this approach may aid in the development of new routes of ambient electrocatalytic CH4 functionalization to achieve production from natural gas resources with minimal infrastructure reliance.
POTENTIAL APPLICATIONS
- Environmental air control
- Novel chemistry synthesis routes
- Methane conversion
- Chemical feedstock generation
ADVANTAGES
- Reactions occur at mild temperatures
- Low activation energy
- High kinetic rate constant
- High reaction selectivity
- Reactions occur at ambient pressures
DEVELOPMENT TO DATE
First successful demonstration by the use of electrochemistry at mild temperatures using AgII as metalloradical for CH4 functionalization.
RELATED PAPERS
Xiang, D.; Iñiguez, J. A.; Deng, J.; Guan, X.; Martinez, A.; Liu, Chong “AgII-Mediated Electrocatalytic Ambient CH4 Functionalization Inspired by HSAB Theory”. Angewandte Chemie International Edition. (2021) 60, 2-12.