Nanoscale Shape and Size Control of Cubic, Cuboctahedral, and Octahedral Cu−Cu₂O Core−Shell Nanoparticles on Si(100) by One-Step, Templateless, Capping-Agent-Free Electrodeposition

Abstract

Cu-Cu2O core-shell nanoparticles (NPs) of different shapes over an extended nanosize regime of 5-400 nm have been deposited on a H-terminated Si(100) substrate by using a simple, one-step, templateless, and capping-agent-free electrochemical method. By precisely controlling the electrolyte concentration [CuSO4 x 5H2O] below their respective critical values, we can obtain cubic, cuboctahedral, and octahedral NPs of different average size and number density by varying the deposition time under a few seconds (<6 s). Combined glancing-incidence X-ray diffraction and depth-profiling X-ray photoelectron spectroscopy studies show that these NPs have a crystalline core-shell structure, with a face-centered cubic metallic Cu core and a simple cubic Cu2O shell with a CuO outerlayer. The shape control of Cu-Cu2O core-shell NPs can be understood in terms of a diffusion-limited progressive growth model under different kinetic conditions as dictated by different [CuSO4 x 5H2O] concentration regimes.

Communication: A density functional investigation of structure-property evolution in the tetrakis hexahedral C4Al14 nanocluster

“…The conventional image tends to be that of a (roughly) spherical core-shell ensemble, although alternative shapes are now known to be important, particularly in light of their potential applications in diverse areas such as nanoelectronics and biomedical sensors. [8][9][10][11] In our previous studies on core-shell C n Al 12 species, the n = 4 system has exhibited a unique behaviour. The original Al 12 shell generally preserved its near-icosahedral structure for n = 1 to 3, but, apparently due to an "oversized" carbon core, acquired a tetracapped-cube-like geometry for C 4 Al 12 .…”

Facile Synthesis of Cu/Cu2O Nanoparticles–Graphene Composites for Efficient Detection of NO2 at Room Temperature

“…1 28 The prominent peaks at 43.3 and 50.4 correspond to the (111) and (200) planes of face centered cubic Cu (JCPDS No. 04-0836) planes, 29 respectively. The peak at 25.5 in the spectra in CuGC2 and CuGC3 can be assigned to graphene, in which the graphene peak is attributed to the (002) plane of hexagonal graphite structure.…”

Cuprous oxide/titanium dioxide nanotube-array with coaxial heterogeneous structure synthesized by multiple-cycle chemical adsorption plus reduction method

“…According to the crystal growth theory, particles tended to grow along the high-energy crystal planes that have higher surface free energy, with the purpose to reduce the surface free energy by eliminating these crystal planes. For Cu 2 O monocrystal, by adjusting the precursor such as copper ion and reductant concentration, the growth rate along the [100] direction relative to that of the [111] direction could be varied owing to the change of surface free energy of crystal plane in different concentrations [32,33]. Therefore, Cu 2 O crystals with different crystal plane direction on each side of the tube wall were obtained.…”