Tuning Pore Geometry of Zirconium Metal-Organic Frameworks via Bent Ligands for Enhanced Sulfide Oxidation Catalysis.

Pore engineering represents a powerful strategy to tailor the physicochemical properties of metal-organic frameworks (MOFs), yet the structure-activity relationship linking pore geometry to catalytic performance remains poorly understood for zirconium-based MOFs (Zr-MOFs). Herein, we report a new Zr-MOF (PCN-1010), featuring a scu topology with channel-type porosity via ligand conformational bending. Distinct from the ftw-topology Zr-MOF with cage-type porosity constructed from a straight tetra-topic ligand, PCN-1010 contains 8-connected Zr6 clusters with more accessible catalytic sites and open one-dimensional (1D) channels. The bent conformation of the linker creates alternating concave and convex surfaces along the c-axis, facilitating the accessibility of the active sites. In addition, PCN-1010 exhibits high chemical stability in various organic solvents owing to the robust zirconium-oxo coordination. As a catalytic platform for sulfide oxidation, PCN-1010, integrated with 12-tungstophosphoric acid, delivers high-selectivity sulfone production with a yield of 97% instead of sulfoxide at room temperature, alongside good recyclability and broad substrate compatibility. The enhanced catalytic performance of PCN-1010 relative to its cage-type ftw counterpart demonstrates that rational pore geometry regulation via ligand bending is an effective route to optimize mass transport and active-site accessibility.