In Situ Structure Evolution from Cu(OH)₂ Nanobelts to Copper Nanowires

Abstract

In situ structural evolution from Cu(OH) 2 nanobelts to copper nanowires has been studied by transmission electron microscopy in a vacuum of 3 × 10 -8 Torr. The decomposition follows the sequence of Cu(OH) 2 f CuO f Cu 2 O f Cu. The decomposition from Cu(OH) 2 to CuO is attributed to electron beam radiation damage. The reduction from CuO to Cu 2 O is attributed to heat-induced decomposition between 50 and 200 °C. For the Cu(OH) 2 nanobelts synthesized using the copper grid with and without a carbon coating, the decomposition from Cu 2 O to Cu takes place between 200 and 300 °C and 300 and 600 °C, and the final Cu takes the forms of polycrystalline nanowires sheathed with graphitic carbon and nanoparticles, respectively. Therefore, because of the nanostructured nature of the nanowires and large surface area, introducing carbon into the sample synthesis can reduce the decomposition temperature by almost half. This study demonstrates a possible approach for creating metallic copper nanowires by heat-induced decomposition under vacuum at 300 °C or even lower.

Synthesis of copper–niobium carbide composite powder by in situ processing

“…X-ray peak for Cu 2 O formation which is close to NbC main peak is not evident in powders milled for 31 h, 42 h and 54 h after heat-treatment at 900 • C. This suggests that when the temperature is increased, decomposition from Cu 2 O to Cu takes place. This explanation is supported by Wang et al [11] who observed that Cu 2 O decomposes to Cu at temperatures ranging between 200 • C and 600 • C. Fig. 5(b) shows that the grey spot (point X) in the microstructure consist of high percentage of Nb (20.85 wt%) and C (19.26 wt%) besides of Cu (61.72 wt%) and O (5.96%).…”

Synthesis of single-crystal β-Ni(OH)2 nanodisks and α-Fe2O3 nanocrystals in C2H5OH–NaOH–NH3⋅H2O system

“…In recent years, synthesis and fabrication of low-dimensional nanostructured materials, such as nanorods, nanowires, nanoplatelets, and nanotubes, have received much research interest due to their outstanding physical and chemical properties [1][2][3][4][5].…”

Synthesis of malachite nanoparticles and their evolution during transmission electron microscopy

“…Further decomposition to Cu 2 O and finally to copper may occur at elevated temperature under vacuum [16]:…”