Sun Xiaoxu
Jiangsu Key Laboratory of New Power Batteries, School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, China.
Front Chem. 2021 Aug 19;9:734460. doi: 10.3389/fchem.2021.734460. eCollection 2021.
The CO electrochemical reduction reaction (CORR) has been a promising conversion method for CO utilization. Currently, the lack of electrocatalysts with favorable stability and high efficiency hindered the development of CORR. Nitrogen-doped graphene nanocarbons have great promise in replacing metal catalysts for catalyzing CORR. By using the density functional theory (DFT) method, the catalytic mechanism and activity of CORR on 11 types of nitrogen-doped graphene have been explored. The free energy analysis reveals that the zigzag pyridinic N- and zigzag graphitic N-doped graphene possess outstanding catalytic activity and selectivity for HCOOH production with an energy barrier of 0.38 and 0.39 eV, respectively. CO is a competitive product since its free energy lies only about 0.20 eV above HCOOH. The minor product is CHOH and CH for the zigzag pyridinic N-doped graphene and HCHO for zigzag graphitic N-doped graphene, respectively. However, for Z-pyN, CORR is passivated by too strong HER. Meanwhile, by modifying the pH value of the electrolyte, Z-GN could be selected as a promising nonmetal electrocatalyst for CORR in generating HCOOH.
CO电化学还原反应（CORR）一直是一种很有前景的CO利用转化方法。目前，缺乏具有良好稳定性和高效率的电催化剂阻碍了CORR的发展。氮掺杂石墨烯纳米碳在替代金属催化剂催化CORR方面具有很大潜力。通过使用密度泛函理论（DFT）方法，研究了11种氮掺杂石墨烯上CORR的催化机理和活性。自由能分析表明，锯齿形吡啶氮和锯齿形石墨氮掺杂石墨烯对HCOOH生成具有出色的催化活性和选择性，能垒分别为0.38和0.39 eV。CO是一种竞争性产物，因为其自由能仅比HCOOH高约0.20 eV。对于锯齿形吡啶氮掺杂石墨烯，次要产物分别是CHOH和CH；对于锯齿形石墨氮掺杂石墨烯，次要产物是HCHO。然而，对于Z-pyN，CORR因过强的析氢反应（HER）而钝化。同时，通过调节电解质的pH值，Z-GN可被选为CORR生成HCOOH的一种有前景的非金属电催化剂。
