Fe/N/C catalysts have been investigated as promising non-noble metal catalysts for both CO₂ reduction reaction (CO₂RR) and oxygen reduction reaction (ORR). However, it is unclear whether both reactions hold the same active sites. In this study, the Fe/N/C catalysts were subjected to oxidation treatment in O₂ at different temperatures to tune the reactivity. It was found that the oxidation treatment exhibits inverse effects on the CO₂RR and ORR. The CO₂RR activity was enhanced while ORR activity was suppressed after the oxidation treatment at temperatures from 80 to 240 °C. This result indicates that CO₂RR and ORR occur at different active sites. Furthermore, it was evidenced that pyrrolic N increases significantly upon the oxidation treatment, similar to the variation tendency of the CO₂RR activity, which suggests that pyrrolic N is highly relevant to the CO₂RR on Fe/N/C catalysts.

已经研究了Fe / N / C催化剂作为用于CO ₂还原反应（CO ₂ RR）和氧还原反应（ORR）的有前途的非贵金属催化剂。但是，尚不清楚两个反应是否都具有相同的活性位点。在这项研究中，Fe / N / C催化剂在O _2中于不同温度下进行了氧化处理，以调节反应性。已经发现，氧化处理对CO ₂ RR和ORR具有相反的作用。在80至240°C的温度下进行氧化处理后，CO ₂ RR活性增强，而ORR活性受到抑制。该结果表明CO ₂RR和ORR发生在不同的活动站点。此外，已证明，在氧化处理后，吡咯N显着增加，类似于CO ₂ RR活性的变化趋势，这表明吡咯N与Fe / N / C催化剂上的CO ₂ RR高度相关。