Kamiya Kazuhide, Kuwabara Akito, Harada Takashi, Nakanishi Shuji
Department of Chemical Science and Engineering Graduate School of Engineering Science, Osaka University 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan.
Research Center for Solar Energy Chemistry, Osaka University 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan.
Chemphyschem. 2019 Mar 4;20(5):648-650. doi: 10.1002/cphc.201801207. Epub 2019 Feb 6.
The high-valence iron species (Fe(IV)=O) in the cytochrome P450 enzyme superfamily is generated via the activation of O , and serves as the active center of selective hydrocarbon oxidation reactions. Furthermore, P450 can employ an alternate route to produce Fe(IV)=O, even from H O without O activation. Meanwhile, Fe(IV)=O has recently been revealed to be the reactive intermediate during H O oxidation to O on hematite electrodes. Herein, we demonstrated the generation of Fe(IV)=O on hematite electrodes during the electrochemical oxidative decomposition of H O using in situ UV-visible absorption spectra. The generation of Fe(IV)=O on hematite electrodes from H O exhibited 100 mV lower overpotential than that from H O. This is because H O serves not only as the oxygen source of Fe(IV)=O, but also as the additional oxidant. Finally, we confirmed that the Fe(IV)=O generated on hematite electrodes can serve as the catalytic site for styrene epoxidation reactions.
细胞色素P450酶超家族中的高价铁物种（Fe(IV)=O）是通过O的活化产生的，并作为选择性烃氧化反应的活性中心。此外，P450甚至可以采用另一种途径，在不进行O活化的情况下从H O生成Fe(IV)=O。同时，最近发现Fe(IV)=O是赤铁矿电极上H O氧化为O过程中的反应中间体。在此，我们利用原位紫外-可见吸收光谱证明了在H O的电化学氧化分解过程中赤铁矿电极上生成了Fe(IV)=O。从H O在赤铁矿电极上生成Fe(IV)=O的过电位比从H O生成时低100 mV。这是因为H O不仅作为Fe(IV)=O的氧源，还作为额外的氧化剂。最后，我们证实了在赤铁矿电极上生成的Fe(IV)=O可以作为苯乙烯环氧化反应的催化位点。
