title: Morphological tuning, self-assembly and optical properties of indium oxide nanocrystals.
abstract: In this paper, weak acids, weak bases or their mixtures were used as reaction media/coordinating ligands to achieve systematic morphological control over amphoteric indium oxide nanostructures. Different indium/oleic acid molar ratios from 1 : 0, 1 : 1, 1 : 2, 1 : 3, 1 : 6 and 1 : 15 in non-coordinating, weakly coordinating, strongly coordinating and their mixed media were adopted to prepare irregular aggregated nanoparticles and uniform regular/truncated octahedra, etc. In addition to their strong size-dependent absorption, single-crystalline indium oxide octahedra also gave a strong band-edge emission while irregular indium oxide aggregated nanoparticles only exhibited a weak deep-trap emission. Meanwhile, the truncated octahedra were self-assembled into either zigzag lines or pentagram patterns, and the regular octahedra and truncated cubes were self-assembled into hexagonally packed nanocrystal arrays. In addition, the formation mechanism of the various nanostructures under different conditions was investigated in detail.
authors.affiliation: Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 3 Research Link, Singapore 117602.
authors.forename: Enyi
authors.initials: E
authors.lastname: Ye
authors.forename: Shuang-Yuan
authors.initials: SY
authors.lastname: Zhang
authors.forename: Suo Hon
authors.initials: SH
authors.lastname: Lim
authors.forename: Shuhua
authors.initials: S
authors.lastname: Liu
authors.forename: Ming-Yong
authors.initials: MY
authors.lastname: Han
mesh_terms: D000588:Amines / Q000737:chemistry; D007204:Indium / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D049329:Nanostructures / Q000737:chemistry / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods*; D019301:Oleic Acid / Q000737:chemistry; D010316:Particle Size; D013053:Spectrophotometry; D013499:Surface Properties; D013696:Temperature
chemical_list: D000588:Amines; D007204:Indium; D019301:Oleic Acid; C047711:indium oxide; C038229:tri-N-octylamine