Surpassing stoichiometric limitation for supra-multi-molar adsorption and separation of acid gases
Guanqing Zhang, F. Liu, Shouchao Zhong, Fujian Liu, Qiliang Zhu, Yu Tang, Jingyi Tan, Anmin Zheng, Lilong Jiang, Feng‐Shou Xiao, Lilong Jiang, Feng‐Shou Xiao
Abstract
Capture of acid gases holds crucial importance for addressing air pollution and climate change, where achieving a molar ratio for adsorption and separation of acid gases on an active site higher than 1.0 remains challenging. Herein, we demonstrate that three nitrogen-bonded one Zn sites within a single-crystalline-like porous carbon (Zn-N3@SC-PC) derived from controlled carbonization of ZIF-8-C ≡ N with KCl, exhibit supra-multi-molar adsorption for CO2, COS, and H2S, even to 1:6 ratio for SO2 on the Zn-N3. This exceptional performance is attributed to the protruded structure in the Zn-N3@SC-PC for more coordination between Zn vacant orbital and acid gases evidenced by DFT calculation and in situ EXAFS. The high capacity for capturing acid gases on this adsorbent is crucial for future in carbon neutrality and environment protection. The Zn-N3 on Zn-N3@SC-PC breaks 1:1 stoichiometric interaction rule with acid gases due to its protruded structure for more coordination between Zn vacant orbital and acid gases, thus exhibiting supra-multi-molar adsorption phenomena (SO2/Zn-N3 = 6:1).