Solution-phase hierarchical self-organization of ultralong Se nanowires into diverse macroarchitectures and their enhanced field emission

Abstract

A simple solution-phase route was developed for the large-scale synthesis of self-organized, closely packed ultralong single crystalline Se nanowire superstructures with diverse morphologies and macroscopic dimensions even extending over several millimeters. The hierarchical architectures of self-organized Se nanowires were formed by reducing H2SeO4 with a bisubstituted aniline, such as 3,5-dimethoxyaniline, 2,5-dimethoxyaniline, 2,6-dimethoxyaniline, and 2-methoxy-5-nitroaniline under solvothermal conditions. Scanning electron microscopy studies show 100% morphological yield and morphological uniformity of the self-organized hierarchical architectures. Based on the dependence of the Se nanostructures on the synthetic conditions, especially the molecular structures of reductants and solvent, we proposed a plausible mechanism to account for the formation of the distinctive morphologies of the self-organized nanowire architectures. The field emission characteristics of the Se nanowires synthesized using 2,6-dimethoxyaniline and 2-methoxy-5-nitroaniline as the reductants are studied. These well-aligned Se nanowires show very low turn-on field (Eto) and threshold field (Ethr) as well as high emission current densities under low applied electric fields, which are superior to most of the one-dimensional (1D) nanostructures reported previously, due to their exceptional aspect ratios (>20 000) and sharp tips in combination with the nature of low band gap and high conductivity of Se. Furthermore, the Se nanowire emitters exhibit good emission current stability with small fluctuations (typically, less than 3%) over a period of 1000 min.

Highly Doped Carbon Nanobelts with Ultrahigh Nitrogen Content as High‐Performance Supercapacitor Materials

“…Materials Synthesis—N–O – CNBs : The self‐organized Se@PMNA core‐shell NW precursor was synthesized by a modified route as described in one recent report . Typically, 35.0 mL of a pyridine solution containing 0.8 mmol of 2‐methoxy‐5‐nitroaniline was added to 5.0 mL of an aqueous solution containing H 2 SeO 4 (0.08 m ) and acetic acid (0.08 m ).…”

Low temperature self-assembled synthesis of hexagonal plate-shape Mn3O4 3D hierarchical architectures and their application in electrochemical capacitors

“…[1][2][3][4] Nevertheless, control over hierarchically structured materials still remains one of the most enormous challenges and an essential requirement for their fundamental understanding and practical applications. [1][2][3][4] Nevertheless, control over hierarchically structured materials still remains one of the most enormous challenges and an essential requirement for their fundamental understanding and practical applications.…”

“…Mn 3 O 4 is commonly prepared by high-temperature calcinations in air (>800 °C) of manganese powders or manganese oxides. 3 Ahmed et al prepared Mn 3 O 4 hexagonal nanosheets via a precipitation route. [15][16][17][18] Recently, developing a simple, low-temperature solution chemical synthetic technique for shape-controlled Mn 3 O 4 materials is of great importance.…”

Dynamics at the crystal-melt interface in a supercooled chalcogenide liquid near the glass transition

“…This result suggests that the atomic motion associated with X-ray beam induced crystallization is a thermally activated process. The polycrystalline diffraction ring observed at the two different q-values correspond to the reflections from (001) and (101) lattice planes of Se 18 , indicating the formation of Se crystallites near Tg in both Se and AsSe 4 samples. The calculated lattice parameters of a = 0.446 nm and c = 0.499 nm, agree well with the literature values reported for trigonal Se 6 .…”