Xie Zeming, Chen Mingwei, Peera Shaik Gouse, Liu Chao, Yang Hui, Qi Xiaopeng, Kumar Uppalapati Pramod, Liang Tongxiang
Engineering Research Center for Hydrogen Energy Materials and Devices, Faculty of Materials Metallurgy and Chemistry, Jiangxi University of Science and Technology, Ganzhou 341000, China.
Department of Environmental Science and Engineering, Keimyung University, Daegu 42601, Republic of South Korea.
ACS Omega. 2020 Mar 6;5(10):5142-5149. doi: 10.1021/acsomega.9b04146. eCollection 2020 Mar 17.
Both theory and experiment show that sp carbon nanomaterials doped with N have great potential as high-efficiency catalysts for oxygen reduction reactions (ORR). At present, there are theoretical studies that believe that C-sites with positive charge or high-spin density values have higher adsorption capacity, but there are always some counter examples, such as the N-doped graphene nanoribbons with edge defects (ND-GNR) of this paper. In this study, the ORR mechanism of ND-GNR was studied by density functional theory (DFT) calculation, and then the carbon ring resonance energy was analyzed from the perspective of chemical graph theory to elucidate the cause and distribution of active sites in ND-GNR. Finally, it was found that the overpotential of the model can be adjusted by changing the width of the model or dopant atoms while still ensuring proper adsorption energy (between 0.5 and 2.0 eV). The minimum overpotential for these models is approximately 0.36 V. These findings could serve as guidelines for the construction of efficient ORR carbon nanomaterial catalysts.
理论和实验均表明，掺杂氮的sp型碳纳米材料作为氧还原反应（ORR）的高效催化剂具有巨大潜力。目前，有理论研究认为，带正电荷或高自旋密度值的C位点具有更高的吸附能力，但总是存在一些反例，比如本文中的具有边缘缺陷的氮掺杂石墨烯纳米带（ND-GNR）。在本研究中，通过密度泛函理论（DFT）计算研究了ND-GNR的ORR机理，然后从化学图论的角度分析了碳环共振能量，以阐明ND-GNR中活性位点的成因和分布。最后发现，在仍确保适当吸附能（0.5至2.0 eV之间）的同时，通过改变模型宽度或掺杂原子可以调节模型的过电位。这些模型的最小过电位约为0.36 V。这些发现可为构建高效ORR碳纳米材料催化剂提供指导。
