Low-Temperature Transformation of Methane to Methanol on Pd₁O₄Single Sites Anchored on the Internal Surface of Microporous Silicate

Direct conversion of methane to chemical feedstocks such as methanol under mild conditions is a challenging but ideal solution for utilization of methane. Pd₁O₄single-sites anchored on the internal surface of micropores of a microporous silicate exhibit high selectivity and activity in transforming CH₄to CH₃OH at 50–95 °C in aqueous phase through partial oxidation of CH₄with H₂O₂. The selectivity for methanol production remains at 86.4 %, while the activity for methanol production at 95 °C is about 2.78 molecules per Pd₁O₄site per second when 2.0 wt % CuO is used as a co-catalyst with the Pd₁O₄@ZSM-5. Thermodynamic calculations suggest that the reaction toward methanol production is highly favorable compared to formation of a byproduct, methyl peroxide.