Dimethyl carbonate (DMC) is an important green chemical widely used in fuel additives, lithium-ion battery electrolytes, biomedicine, and organic synthesis. Current DMC production processes mainly rely on energy-intensive thermal catalytic methods, such as methanol oxidative carbonylation and transesterification. However, these traditional processes still face challenges, the development of green and sustainable methods for DMC production is urgently needed.

CO₂ is not only a major greenhouse gas but also an abundant and highly promising carbon resource in nature. Its catalytic conversion into high-value-added chemical DMC can both alleviate environmental pressure and promote carbon resource utilization, significantly contributing to achieving carbon neutrality goals. With the rapid development of renewable electricity, electrosynthesis technology has emerged as a highly promising green route for producing high-value-added chemicals.

In a study published in Angew. Chem. Int. Ed., Prof. CAO Rong and Prof HUANG Yuanbiao from Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, proposed a tandem electrocatalysis strategy for efficient DMC production under ambient conditions.

This strategy utilizes a cobalt polyphthalocyanine framework with single-atom sites and atomically precise palladium-sulfur clusters. The CoPPc-Pd₆S₁₂ tandem catalyst system synergistically activates CO₂ and enhances mass transfer, increasing the local concentration of key intermediates and thereby improving DMC production efficiency.

This tandem system exhibits excellent performance: in a 0.1 M NaBr methanol electrolyte, DMC selectivity reaches 93.4% with a yield of 34.9 mmol L^-1 h^-1; at an electrolyte concentration of 0.5 M, a record current density of 155.2 mA cm^-2 is achieved.

In-situ generated CO and methoxy species on CoPPc are effectively transferred to Pd-S sites, enabling intermediate stabilization and optimal coupling orientation, thus enhancing DMC selectivity and current density.

Theoretical calculations indicate that the CoPPc-Pd₆S₁₂ system lowers the energy barrier for C-O coupling, promoting DMC formation.

This study provides an efficient tandem electrocatalysis system for high-selectivity, high-current-density DMC production from CO₂.

Schematic diagram of DMC synthesis processes(Image by Prof. CAO’s group)

Contact:

Prof. CAO Rong

Fujian Institute of Research on the Structure of Matter,

Chinese Academy of Sciences

Email: rcao@fjirsm.ac.cn