Controlled Synthesis and Self-Assembly of Single-Crystalline CuO Nanorods and Nanoribbons

Abstract

We report several wet-chemical methods for synthesis of one-dimensional CuO nanostructures in water-ethanol mixed solvents at 77-82 °C and 1 atm. Single-crystalline monodispersed CuO nanorods with a selected breadth in the range of 5-15 nm have been prepared by controlling reagent concentrations. The nanorods are preferentially grown along 〈010〉 directions. A two-step continuous process has also been developed to prepare CuO nanorods and ribbons (length up to 1 µm) with a large aspect ratio under pseudo-steady-state operation. Furthermore, a two-dimensional netted structure has been assembled for the first time from short nanorods formed after prolonged aging; the nanorods are attached each other using their {001}, {100}, and {110} crystal planes. With concentrated NaOH used in synthesis, the nanorods can also be extended along 〈100〉, which gives rise to the formation of CuO nanoplatelets. Various synthetic parameters have also been investigated.

Structural refinement and photoluminescence properties of irregular cube-like (Ca1−xCux)TiO3 microcrystals synthesized by the microwave–hydrothermal method

“…Moreover, the self-assemble of these plates is favored in some energetic crystallographic planes. Therefore, the micro-cubes will grow from aggregation and selfassemble of these plates along the (100) and (010) directions [60]. As the concentration of Cu 2þ increases to 0.02, the presence of copper ions in the reactional media promotes the increase of the electrostatic interaction between the ions.…”

Emergent methods to synthesize and characterize semiconductor CuO nanoparticles with various morphologies – an overview

“…For this method Cu(OH) 2 nanoribbons were obtained which was confirmed by SEM and TEM images (figure 16). The exact reactions for the selective formation of Cu(OH) 2 Zeng et al [39] reported synthesis of CuO nanorods and nanoribbons by wet chemical method in which water-ethanol mixture is used as a solvent. 40 ml of Cu(NO 3 ) 2 Á 3H 2 O (0.01 M in pure ethanol) was slowly added at a rate of 0.1 ml/min using a mechanically pumped syringe to 40 ml of NaOH (0.5 M in ethanol) solution under stirring in a Teflon flask at 65 C and the resultant product was then aged together with mother liquor at the same temperature for 12-36 h respectively.…”

Effect of Ultrasonic‐assisted Preparation Methods on Structure, Morphology and Optical Properties of Nanosized Cupric Oxide

“…Chen et al 18 have reported the synthesis of CuO shuttle-like nanocrystals via the hydrothermal decomposition route using the pre-obtained Cu(OH) 2 as the copper source in the absence of any surfactants. Synthesis of CuO nanorods and nanoribbons at the moderate temperature (77-82 ºC) in water-ethanol solutions were also reported by Chang et al 19 Balamurugan et al 20 reported the synthesis of nanosized CuO by the electrodeposition of Cu(II) ions followed by the gas-solid reaction. Kim and co-workers synthesized porous CuO nanowires by deposition of Cu on the porous single-walled carbon nanotube substrate followed by a thermal oxidation process.…”

“…Despite considerable efforts devoted to the preparation of the nanosized CuO, [15][16][17][18][19][20][21][22][23][24][25] there is a lack of information about ultrasonic-assisted (US) preparation methods especially US thermal decomposition and US liquid hydrolysis methods.…”