Highly Efficient Decomposition of Perfluorocarbons for over 1000 Hours via Active Site Regeneration
Hang Zhang, Tao Luo, Yingkang Chen, Kang Liu, Hongmei Li, Evangelina Pensa, Junwei Fu, Zhang Lin, Liyuan Chai, Emiliano Cortés, Min Liu
Abstract
Abstract Tetrafluoromethane (CF 4 ), the simplest perfluorocarbon (PFC), has the potential to exacerbate global warming. Catalytic hydrolysis is a viable method to degrade CF 4 , but fluorine poisoning severely restricts both the catalytic performance and catalyst lifetime. In this study, Ga is introduced to effectively assists the defluorination of poisoned Al active sites, leading to highly efficient CF 4 decomposition at 600 °C with a catalytic lifetime exceeding 1,000 hours. 27 Al and 71 Ga magic‐angle spinning nuclear magnetic resonance spectroscopy (MAS NMR) showed that the introduced Ga exists as tetracoordinated Ga sites (Ga IV ), which readily dissociate water to form Ga−OH. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and density function theory (DFT) calculations confirmed that Ga−OH assists the defluorination of poisoned Al active sites via a dehydration‐like process. As a result, the Ga/Al 2 O 3 catalyst achieved 100 % CF 4 decomposition keeping an ultra‐long catalytic lifetime and outperforming reported results. This work proposes a new approach for efficient and long‐term CF 4 decomposition by promoting the regeneration of active sites.