Feng Jiaqi, Gao Hongshuai, Zheng Lirong, Chen Zhipeng, Zeng Shaojuan, Jiang Chongyang, Dong Haifeng, Liu Licheng, Zhang Suojiang, Zhang Xiangping
Beijing Key Laboratory of Ionic Liquids Clean Process, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, 100190, Beijing, P.R. China.
College of Chemical Engineering, University of Chinese Academy of Science, 100049, Beijing, P.R. China.
Nat Commun. 2020 Aug 28;11(1):4341. doi: 10.1038/s41467-020-18143-y.
Developing effective catalysts based on earth abundant elements is critical for CO electroreduction. However, simultaneously achieving a high Faradaic efficiency (FE) and high current density of CO (j) remains a challenge. Herein, we prepare a Mn single-atom catalyst (SAC) with a Mn-N site embedded in graphitic carbon nitride. The prepared catalyst exhibits a 98.8% CO FE with a j of 14.0 mA cm at a low overpotential of 0.44 V in aqueous electrolyte, outperforming all reported Mn SACs. Moreover, a higher j of 29.7 mA cm is obtained in an ionic liquid electrolyte at 0.62 V overpotential. In situ X-ray absorption spectra and density functional theory calculations demonstrate that the remarkable performance of the catalyst is attributed to the Mn-N site, which facilitates the formation of the key intermediate COOH through a lowered free energy barrier.
开发基于储量丰富元素的高效催化剂对于CO电还原至关重要。然而，同时实现高法拉第效率（FE）和高CO电流密度（j）仍然是一个挑战。在此，我们制备了一种嵌入石墨相氮化碳中的具有Mn-N位点的Mn单原子催化剂（SAC）。在水性电解质中，所制备的催化剂在0.44 V的低过电位下表现出98.8%的CO FE和14.0 mA cm的j，优于所有已报道的Mn SAC。此外，在离子液体电解质中，在0.62 V过电位下可获得更高的29.7 mA cm的j。原位X射线吸收光谱和密度泛函理论计算表明，该催化剂的优异性能归因于Mn-N位点，其通过降低自由能垒促进了关键中间体COOH的形成。
