Li Wenxian, Cui Xiangyuan, Zeng Rong, Du Guodong, Sun Ziqi, Zheng Rongkun, Ringer Simon P, Dou Shi Xue
1] Institute for Superconducting and Electronic Materials, University of Wollongong, NSW 2522, Australia [2] School of Materials Science and Engineering, Shanghai University, Shanghai 200072, PR China [3] Solar Energy Technologies, School of Computing, Engineering and Mathematics, University of Western Sydney, Penrith, NSW 2751, Australia.
1] Australian Centre for Microscopy and Microanalysis, The University of Sydney, NSW 2006, Australia [2] School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, NSW 2006, Australia.
Sci Rep. 2015 Mar 11;5:8987. doi: 10.1038/srep08987.
Modulation of material physical and chemical properties through selective surface engineering is currently one of the most active research fields, aimed at optimizing functional performance for applications. The activity of exposed crystal planes determines the catalytic, sensory, photocatalytic, and electrochemical behavior of a material. In the research on nanomagnets, it opens up new perspectives in the fields of nanoelectronics, spintronics, and quantum computation. Herein, we demonstrate controllable magnetic modulation of α-MnO2 nanowires, which displayed surface ferromagnetism or antiferromagnetism, depending on the exposed plane. First-principles density functional theory calculations confirm that both Mn- and O-terminated α-MnO2 (1 1 0) surfaces exhibit ferromagnetic ordering. The investigation of surface-controlled magnetic particles will lead to significant progress in our fundamental understanding of functional aspects of magnetism on the nanoscale, facilitating rational design of nanomagnets. Moreover, we approved that the facet engineering pave the way on designing semiconductors possessing unique properties for novel energy applications, owing to that the bandgap and the electronic transport of the semiconductor can be tailored via exposed surface modulations.
通过选择性表面工程来调制材料的物理和化学性质是目前最活跃的研究领域之一，旨在优化材料在各种应用中的功能性能。暴露晶面的活性决定了材料的催化、传感、光催化和电化学行为。在纳米磁体的研究中，它为纳米电子学、自旋电子学和量子计算领域开辟了新的前景。在此，我们展示了α-MnO₂纳米线的可控磁调制，其根据暴露平面表现出表面铁磁性或反铁磁性。第一性原理密度泛函理论计算证实，Mn端和O端的α-MnO₂(1 1 0)表面均呈现铁磁有序。对表面可控磁性粒子的研究将在我们对纳米尺度磁性功能方面的基本理解上取得重大进展，有助于合理设计纳米磁体。此外，我们证明了晶面工程为设计具有独特性质的新型能源应用半导体铺平了道路，因为半导体的带隙和电子传输可以通过暴露表面调制来定制。
