Catalan Francesca Celine I, Anh Le The, Oh Junepyo, Kazuma Emiko, Hayazawa Norihiko, Ikemiya Norihito, Kamoshida Naoki, Tateyama Yoshitaka, Einaga Yasuaki, Kim Yousoo
Surface and Interface Science Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
Center for Green Research on Energy and Environmental Materials (GREEN) and International Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, 305-0044, Japan.
Adv Mater. 2021 Oct;33(42):e2103250. doi: 10.1002/adma.202103250. Epub 2021 Sep 6.
Doped diamond electrodes have attracted significant attention for decades owing to their excellent physical and electrochemical properties. However, direct experimental observation of dopant effects on the diamond surface has not been available until now. Here, low-temperature scanning tunneling microscopy is utilized to investigate the atomic-scale morphology and electronic structures of (100)- and (111)-oriented boron-doped diamond (BDD) electrodes. Graphitized domains of a few nanometers are shown to manifest the effects of boron dopants on the BDD surface. Confirmed by first-principles calculations, local density of states measurements reveal that the electronic structure of these features is characterized by in-gap states induced by boron-related lattice deformation. The dopant-related graphitization is uniquely observed in BDD (111), which explains its electrochemical superiority over the (100) facet. These experimental observations provide atomic-scale information about the role of dopants in modulating the conductivity of diamond, as well as, possibly, other functional doped materials.
几十年来，掺杂金刚石电极因其优异的物理和电化学性能而备受关注。然而，到目前为止，尚未有关于掺杂剂对金刚石表面影响的直接实验观察。在此，利用低温扫描隧道显微镜研究（100）和（111）取向的硼掺杂金刚石（BDD）电极的原子尺度形貌和电子结构。结果表明，几纳米的石墨化区域体现了硼掺杂剂对BDD表面的影响。通过第一性原理计算证实，态密度局部测量结果表明，这些特征的电子结构以硼相关晶格变形诱导的带隙态为特征。在BDD（111）中独特地观察到了与掺杂剂相关的石墨化现象，这解释了其相对于（100）面的电化学优势。这些实验观察提供了关于掺杂剂在调节金刚石电导率以及可能在其他功能性掺杂材料中作用的原子尺度信息。
