High-Pressure Electro-Fenton Driving CH₄ Conversion by O₂ at Room Temperature

Electrochemical conversion of CH4 to easily transportable and value-added liquid fuels is highly attractive for energy-efficient CH4 utilization, but it is challenging due to the low reactivity and solubility of CH4 in the electrolyte. Herein, we report a high-pressure electro-Fenton (HPEF) strategy to establish a hetero-homogeneous process for the electrocatalytic conversion of CH4 by O-2 at room temperature. In combination with elevation of reactant pressure to accelerate reaction kinetics, it delivers an unprecedented HCOOH productivity of 11.5 mmol h(-1) g(Fe)(-1) with 220 times enhancement compared to that under ambient pressure. Remarkably, an HCOOH Faradic efficiency of 81.4% can be achieved with an ultralow cathodic overpotential of 0.38 V. The elevated pressure not only promotes the electrocatalytic reduction of O-2 to H2O2 but also increases the reaction collision probability between CH4 and center dot OH, which is in situ generated from the Fe2+-facilitated decomposition of H2O2.