GaP/GaO_x Core−Shell Nanowires and Nanochains and Their Transport Properties

Abstract

GaP/GaO x core-shell nanowires and nanochains have been synthesized in a large quantity by thermal evaporation of mixture of GaP and Ga powders at high temperature. The as-synthesized products were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Microstructure analysis indicates that both products are composed of GaP nanowires and GaO x amorphous shells. Their growth directions are along face-centered-cubic (fcc) GaP <11 j 1> direction with high density twins. The transport properties were also investigated by patterning the core-shell nanowires and nanochains on Si/SiO 2 substrates. The characteristic I-V curves demonstrated good conductivity for the core-shell nanowires and nanochains, but a field-effect property was only observed in the core-shell nanowires. A distinct response between the core-shell nanowire and nanochain devices was observed under an illumination of an ultraviolet light, which might be attributed to the nature of the nanowires and nanochains.

Fabrication and visible emission of single-crystal diameter-modulated gallium phosphide nanochains

“…Among them, chainlike morphology has attracted special attention because of their significance to investigate the electrons and photons behaviors in the diameter-modulated 1D nanostructure and their potential applications in novel nanodevices. 16,17 Gallium phosphide ͑GaP͒ is an important semiconductor with a band gap of 2.26 eV and has been widely used in the red LEDs and other optoelectronic devices. 18 Recently, an increasing attention has been paid to controllably fabricate 1D GaP nanostructures for their potential applications for optoelectronics, field emitters, and LED devices.…”

“…24 Most of these syntheses involve gold nanocrystals act as catalysts to induce the growth of these 1D nanostructures, such as nanowires, nanobelts, and their heterostructures via a conventional vapor-liquid-solid growth mechanism. 18,20,22,[24][25][26][27][28][29] Thereinto, GaP/ GaO x core-shell nanochains, as a special heterostructures, were fabricated by high temperature thermal evaporation of GaP and Ga powders, 16 or of GaN and phosphorus powders. 30 Their elec-trical transport properties have been confirmed to be different from those of the smooth GaP nanowires.…”

Synthesis and Growth Mechanism of SiC/SiO2 Nanochains Heterostructure by Catalyst‐Free Chemical Vapor Deposition

“…In fact, not only the SiC/SiO 2 nanochains but also B 4 C/SiO x , GaP/GaO x , Boron/SiO 2 , SiC/C, Si/C, and CNTs/C nanochains heterostructures were synthesized very recently and their formation mechanisms were also discussed by reporters. [29][30][31][32][33] Researches have paid their considerable effort to explain the phenomenon which can be used to synthesize the attractive nanochains. 3,12,[29][30][31][32][33] H. Ni and his co-work attributed the SiO 2 beads formed on boron strings to the supersaturation and drop cycle of SiO vapor pressures.…”

“…[29][30][31][32][33] Researches have paid their considerable effort to explain the phenomenon which can be used to synthesize the attractive nanochains. 3,12,[29][30][31][32][33] H. Ni and his co-work attributed the SiO 2 beads formed on boron strings to the supersaturation and drop cycle of SiO vapor pressures. 31 Preferential nucleation and growth of residual SiO 2 beads around the SiC nanowires defects was accounted as the formation cause of SiC/SiO 2 nanochains in Li et al 12 However, most of the authors think that the forming process of the amorphous beads utilizes Rayleigh instability of secondary adhesive viscous materials, which is similarly employed to interpret the growth mechanism of the as-received SiC/SiO 2 nanochains.…”

Remarkably flexible quinazolinones—synthesis and biological applications

“…Numerous synthetic routes have been reported for the acid catalyzed preparation of quinazolinones (as shown in 1), that is, quinazolin-4(3H)-ones can be prepared from the derivatives of 2-aminobenzaldehyde, 2-aminophenyl ketones, or anthranilic acids at moderate to elevated temperatures. [6][7][8] Recently, various metal and non-metal-based reagents including Yb (OTf) 3, [9] iridium, [10] gallium trifluoromethane sulfonate, [11] copper chloride, [12] TiCl 4 /Zn, [13] citric acid [14] [bmim]HSO 4, [15] halogens (for example, iodine), [16] ammonium chloride, [17] ionic liquids, [18] Brönsted acids, [19] phosphoric acid, [20] and tetra butyl ammonium bromide [21] were reported for the synthesis of various derivatives of quinazolinones. The significance of urea/thiourea as a reactant is very well-known in organic synthesis as per the Biginelli reaction [22,23] due to effective ammonia surrogate from urea/thiourea in the formation of quinazolin-4(3H)one ring, leading to a straight forward and inexpensive preparation of quinazoline-4(3H)-ones (6) and 2-substituted 2,3-dihydroquinazolin-4(1H)-ones (21) from the reaction of an aldehyde with isatoic anhydride 20 driven by the presence of urea/thiourea (Scheme 1).…”