대기압의 공기 분위기에서 열증발법에 의해 합성된 가지상 구조의 MgO 나노선

• Published in: 대한금속재료학회지 Vol. 61; no. 6; pp. 444 - 448
• Main Authors: 이근형, Geun-hyoung Lee
• Format: Journal Article
• Language: Korean
• Published: 대한금속재료학회 05.06.2023
• Subjects: air; atmospheric pressure; branched nanowires; magnesium oxide; thermal evaporation
• ISSN: 1738-8228
• DOI: 10.3365/KJMM.2023.61.6.444

MgO nanowires with a branched structure were fabricated using a thermal evaporation method in air at atmospheric pressure. The branched MgO nanowire was made up of two parts: a primary central nanowire trunk and lots of secondary nanowire branches. The branched MgO nanowires had a 4-fold symmetrical structure. The secondary nanowire branches grew perpendicular on the four side facets of the central nanowire trunks with square cross-sections. The nanowire branches also grew in a single row and were vertically well aligned in the same direction with each other. The scanning electron microscopy images of the branched nanowires grown at 1000℃ showed that the diameter of branches gradually decreased along the growth direction and no catalyst particle was found at the tips of the branches, indicating that the branches were grown by a vapor-solid process. For the branched nanowires grown at 1150℃, spherical particles which were shown to be catalysts were observed at the tips of the branches. The chemical analysis by energy dispersive spectroscopy showed that the spherical particles were composed of Mg and O elements. These results suggest that the branches’ growth resulted from a self-catalyzed vapor-liquid-solid process. The structural characterization by X-ray diffraction confirmed that the branched MgO nanowires had a cubic lattice structure. The room temperature cathodoluminescence spectra of the branched MgO nanowires exhibited a very strong visible emission which was associated with oxygen vacancies. (Received 10 January, 2023; Accepted 23 February, 2023)