Triazine‐based multicomponent metallacages with tunable structures for SO₂ selective capture and conversion

Abstract

The design of novel materials for sulfur dioxide (SO2) capture and conversion with considerable efficiency under mild conditions is of great significance for human health and environmental protection yet highly challenging. Herein, we report a series of triazine‐based multicomponent metallacages via coordination‐driven self‐assembly of 2,4,6‐tri(4‐pyridyl)‐1,3,5‐triazine, cis‐Pt(PEt3)2(OTf)2 and different tetracarboxylic ligands. As the increase of the length of the tetracarboxylates, the structures of the metallacages change from pyramids to extended octahedrons. Owing to their N‐rich structure, these metallacages are further used for selective SO2 capture, showing good adsorption capacity and remarkable SO2/CO2 selectivity in ambient conditions, suggesting their potential applications toward real flue gas desulfurization. The metallacages are further employed for the conversion of SO2 into value‐added compounds, showing exceptional efficiency even dilute SO2 is used as the reactant. This study represents a type of structure‐tunable triazine‐based metallacages for SO2 capture and conversion, which will pave the way on the applications of metal‐organic complexes for gas adsorption.

High-Performance Porous Organic Polymers for Environmental Remediation of Toxic Gases

“…Similar guest–guest interaction between two adjacent SO 2 molecules has been reported for MOF MFM-520 and for fluorinated anion-pillared metal–organic frameworks (APMOFs). , Higher binding energy in LDA compared to M06 level of theory as summarized in Table accounts for the overestimation of the binding in the LDA method . Our experimental and calculated binding energies from the M06 level of calculations are in good agreement with the binding energy reported for imidazole (39.1 kJ mol –1 ) by Shannon et al A similar result (40.52 kJ mol –1 ) was reported for SO 2 –tetrazine interaction based on the Monte Carlo simulation . Other reports on SO 2 capture by azole-based ionic liquids, derived from tetrazole and imidazole moieties, demonstrated that the electronegative nitrogen atoms of the anions can modulate bonding strength and lead to high absorption of SO 2 .…”

“… 32 Our experimental and calculated binding energies from the M06 level of calculations are in good agreement with the binding energy reported for imidazole (39.1 kJ mol –1 ) by Shannon et al 76 A similar result (40.52 kJ mol –1 ) was reported for SO 2 –tetrazine interaction based on the Monte Carlo simulation. 77 Other reports on SO 2 capture by azole-based ionic liquids, derived from tetrazole and imidazole moieties, demonstrated that the electronegative nitrogen atoms of the anions can modulate bonding strength and lead to high absorption of SO 2 . 78 The reported calculated enthalpies for SO 2 –tetrazole complexes were 89.3, 59.9, 39.7, and 34.4 kJ mol –1 for [Tetz]@SO 2 , [Tetz]@2SO 2 , [Tetz]@3SO 2 , and [Tetz]@4SO 2 , respectively.…”