Investigation of Electron\nTransfer Properties on Silicalite‑1\nZeolite for Potential Electrocatalytic Applications

To develop high-performance electrocatalysts is critical\nto sustainable\nconversion and storage of renewable energy. Silicalite-1 (S-1) zeolite\nis considered promising for constructing electrocatalysts featuring\nuniform and precise porosity and a stable structural skeleton even\nat extreme potentials. However, its electrochemical properties remain\npoorly understood, particularly regarding the roles of internal pore\nchannels. Herein, inner- and outer-sphere electron transfer (ISET/OSET)\nroutes on the S-1 zeolite were investigated by classical redox probes.\nThe results for the first time revealed that the ISET kinetics inside\nthe pores of S-1 zeolite is more rapid than that on external surfaces,\noptimized by microporous scale channels and terminated hydroxyl groups.\nConversely, the kinetics of the OSET did not closely depend on the\nporosity and surface properties of the S-1 zeolite. These electrochemical\ninsights further initiated a lithium-ion-incorporated S-1 zeolite\nwith rapid ISET kinetics for electrocatalysis of oxygen reduction.\nIt demonstrated a high performance of 85% selectivity for H<sub>2</sub>O<sub>2</sub> production in a neutral solution and a yield of 9.2\nmol g<sub>cat</sub><sup>–1</sup> h<sup>–1</sup> when\nconfigured in a flow cell.