Methane activation by gold-doped titanium oxide cluster anions with closed-shell electronic structures

Area of Science:

• Inorganic Chemistry
• Physical Chemistry
• Materials Science

Background:

• Understanding the reactivity of metal oxide cluster anions is crucial for catalysis.
• Closed-shell species are often considered less reactive, posing a challenge for methane activation.

Purpose of the Study:

• To investigate the reactivity of gas-phase cluster anions AuTi3O7- and AuTi3O8- with methane.
• To elucidate the mechanisms of methane activation and conversion by these cluster anions.

Main Methods:

• Mass spectrometric experiments under thermal collision conditions.
• Quantum chemical calculations to model reaction pathways and intermediates.

Main Results:

• Methane activation was observed for both AuTi3O7- and AuTi3O8- with the formation of AuCH3.
• Formaldehyde formation was identified in the reaction system involving AuTi3O8-.
• Cooperative effects of Au+ and O2- ions were identified as key to C-H bond cleavage.

Conclusions:

• Closed-shell metal oxide species can effectively facilitate thermal H-CH3 bond cleavage in methane.
• The identified mechanisms provide insights into catalytic conversion of methane.
• These findings highlight the potential of specific cluster anion structures in chemical transformations.