Angew. Chem. Int. Ed.: Immobilized Tetraalkylammonium Cations Enable Metal-free CO2 Electroreduction in Acid and Pure Water

Title：

Immobilized Tetraalkylammonium Cations Enable Metal-free CO2 Electroreduction in Acid and Pure Water

Authors：

Jia Fan^1,2,Binbin Pan^1,2, Jialing Wu³, Chaochen Shao^1,2, Zhaoyu Wen^1,2, Yuchen Yan^1,2,Yuhang Wang^1,2* and Yanguang Li^1,2,3*

Institutions：

¹Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou 215123, China

²Jiangsu Key Laboratory for Advanced Negative Carbon Technologies, Soochow University, Suzhou 215123, China

³Macao Institute of Materials Science and Engineering (MIMSE), MUST-SUDA Joint Research Center for Advanced Functional Materials, Macau University of Science and Technology, Taipa 999078, Macau SAR, China

Abstract：

Carbon dioxide reduction reaction (CO₂RR) provides an efficient pathway to convert CO₂ into desirable products, yet its commercialization is greatly hindered by the huge energy cost due to CO₂ loss and regeneration. Performing CO₂RR under acidic conditions containing alkali cations can potentially address the issue, but still causes (bi)carbonate deposition at high current densities, compromising product Faradaic efficiencies (FEs) in present-day acid-fed membrane electrode assemblies. Herein, we present a strategy using a positively charged polyelectrolyte—poly(diallyldimethylammonium) immobilized on graphene oxide via electrostatic interactions to displace alkali cations. This enables a FE of 85%, a carbon efficiency of 93%, and an energy efficiency (EE) of 35% for CO at 100mAcm⁻² on modified Ag catalysts in acid. In a pure-water-fed reactor, we obtained a 78% CO FE with a 30% EE at 100mAcm⁻² at 40°C. All the performance metrics are comparable to or even exceed those attained in the presence of alkali metal cations.

IF：

16.823

Link：

https://onlinelibrary.wiley.com/doi/10.1002/anie.202317828