The direct conversion of methane to methanol would enable better utilization of abundant natural gas resources. In the presence of stoichiometric PtIV oxidants, PtII ions are capable of catalyzing this reaction in aqueous solutions at modest temperatures. Practical implementation of this chemistry requires a viable strategy for replacing or regenerating the expensive PtIV oxidant. Herein, we establish an electrochemical strategy for continuous regeneration of the PtIV oxidant to furnish overall electrochemical methane oxidation. We show that Cl-adsorbed Pt electrodes catalyze facile oxidation of PtII to PtIV at low overpotential without concomitant methanol oxidation. Exploiting this facile electrochemistry, we maintain the PtII/IV ratio during PtII-catalyzed methane oxidation via in situ monitoring of the solution potential coupled with dynamic modulation of the electric current. This approach leads to sustained methane oxidation catalysis with 70% selectivity for methanol.
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机译:将甲烷直接转化为甲醇将可以更好地利用丰富的天然气资源。在化学计量的Pt IV sup>氧化剂存在下,Pt II sup>离子能够在中等温度下的水溶液中催化该反应。该化学方法的实际实施需要一种可行的策略来替代或再生昂贵的Pt IV sup>氧化剂。在此,我们建立了一种连续再生Pt IV sup>氧化剂的电化学策略,以提供整体的电化学甲烷氧化作用。我们显示,Cl吸附的Pt电极在低超电势下催化Pt II sup>易于氧化为Pt IV sup>而没有甲醇氧化。利用这种简便的电化学方法,我们通过原位监测溶液电势并动态调节电流来维持Pt II sup>催化甲烷氧化过程中Pt II / IV sup>的比率。该方法导致持续的甲烷氧化催化,对甲醇的选择性为70%。
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