Mechanocatalytic H2O2 production using ferroelectric KSr2Nb3Ta2O15 nanorods

Abstract

Traditional methods of hydrogen peroxide (H₂O₂) production, such as the anthraquinone process and electrolysis, face challenges including high costs, significant energy consumption, and strict electrode requirements. Therefore, this study proposes a mechanocatalytic approach for H₂O₂ production. By utilizing the molten-salt method, KSr₂Nb₃Ta₂O₁₅ ferroelectric nanorods were synthesized to achieve a mechanocatalytic H₂O₂ yield of 117 μmol/L/h in a glass beaker equipped with a PTFE disk. Remarkably, substituting the glass beaker with a ZrO₂ ball mill for the mechanocatalytic experiments significantly increased the H₂O₂ yield to 820 μmol/L/h. The Piezoelectric Force Microscopy (PFM), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller (BET) analysis revealed that the inherent electric field of ferroelectric materials and the abundant specific surface area on the KSr₂Nb₃Ta₂O₁₅ nanorod surface enhance electron transfer during the mechanocatalytic process. Rotating Ring-Disk Electrode tests indicated that the mechanocatalytic one-step two-electron pathway dominates H₂O₂ generation through mechanocatalysis with an 85 % selectivity rate, surpassing conventional two-step one-electron pathway efficiency in oxygen reduction reaction. Output charge testing of vertical contact separation mode triboelectric nanogenerator (CS-TENG) determines the ability of a material to gain or lose electrons during friction processes. This breakthrough presents a novel and efficient method for H₂O₂ production via mechanocatalysis. Using the molten-salt method, KSr₂Nb₃Ta₂O₁₅ ferroelectric nanorods were synthesized, resulting in a mechanocatalytic H₂O₂ yield of 820 μmol/L/h in a ball mill jar. Comprehensive analysis utilizing PFM, SEM, BET, RRDE, CS-TENG and by comparing the effect of mechanocatalysis with different materials demonstrated that the built-in electric field of ferroelectric materials enhance electron transfer in the mechanocatalytic process. This breakthrough presents a novel and efficient method for H₂O₂ production through mechanocatalysis.