Control in Local Coordination Environment Boosting Activating Molecular Oxygen with an Atomically Dispersed Binary...

Area of Science:

• Catalysis
• Materials Science
• Biomass Conversion

Background:

• Molecular oxygen activation is vital for biological processes and industrial chemistry.
• Developing efficient catalysts for oxygen activation remains a key challenge.
• Biomass conversion offers a sustainable route to valuable chemicals.

Purpose of the Study:

• To design and investigate a Mn-Co dual-single-atom catalyst for enhanced oxygen activation.
• To explore the synergistic effects between different atomic sites in the catalyst.
• To apply the catalyst in the oxidative esterification of 5-hydroxymethylfurfural (HMF).

Main Methods:

• Synthesis of a Mn-Co dual-single-atom catalyst.
• Characterization using Extended X-ray Absorption Fine Structure (EXAFS) analysis.
• Testing the catalyst's performance in the oxidative esterification of HMF.
• Utilizing control experiments to elucidate reaction mechanisms.

Main Results:

• The catalyst demonstrated synergistic oxygen activation via two distinct pathways: superoxide radical formation (Co-N4 sites) and reversible surface oxygen dynamics (Mn-N,O sites).
• EXAFS analysis revealed a favorable Mn-O bond distance (approx. 2.19 Å) facilitating bond cycling.
• The catalyst achieved an excellent yield of 95.8% for the diester product with high carbon balance.
• The dual reactive oxygen species effectively matched the oxidation requirements of HMF's functional groups.

Conclusions:

• The Mn-Co dual-single-atom catalyst effectively leverages synergistic effects for superior oxygen activation.
• The catalyst's unique structure and dual activation pathways enable efficient biomass conversion.
• This work presents a novel strategy for designing diatomic catalysts with enhanced reactivity.