Optical and Photoconductive Response of CuO Nanostructures Grown by a Simple Hot-Water Treatment Method

Abstract

In this work, we report the fabrication and characterization of copper(II) oxide (CuO) nanoleaf structures (NS) grown on Cu sheets by a facile hot-water treatment (HWT) method without using catalyst materials. In addition, simple photoconductive devices based on asprepared CuO nanoleaves were fabricated to study the optical and photocurrent response of CuO NSs. Scanning electron microscopy images revealed the formation of uniform and dense nanoleaves morphology of CuO on Cu sheets. X-ray diffractometer patterns indicated that synthesized nanostructures have a monoclinic CuO structure. Furthermore, X-ray photoelectron spectroscopy results demonstrate the formation of the Cu−O chemical bond which confirmed the formation of the CuO phase. For the fabrication of the photoconductive devices, the CuO/Cu samples were coated with an aluminum-doped ZnO (AZO) shell by sputter deposition at room temperature. CuO NSs show high-broadband ultraviolet/visible spectroscopy (UV/vis) absorbance with marked enhancement after AZO coating. Current density−voltage (J−V) measurements show that AZO/CuO/Cu devices exhibit a photocurrent density response of 9.65 ± 0.43 μA/cm 2 with a rise time of 0.195 s and decay time of 0.192 s. They also indicate a Schottky contact between p-type CuO NSs and the Cu substrate. Photocurrent increases and rise time and decay time decrease with an applied forward bias (e.g. ∼19.00 μA/cm 2 at 1.0 V with a rise time of ∼0.100 s and decay time of 0.096 s). Optical band gap of CuO NSs was calculated to be 1.44 ± 0.13 eV, by the analysis of Tauc's plot. These results indicate that our photoconductive devices based on CuO NSs prepared by HWT can achieve high light absorption and good photocurrent response for optoelectronic applications.

In Situ Growth and UV Photocatalytic Effect of ZnO Nanostructures on a Zn Plate Immersed in Methylene Blue

“…The optical bandgap of the ZnO nanostructures was estimated using UV-Vis diffuse reflectance spectroscopy, Kubelka-Munk function (F(R)), and Tauc plot [31,32]. The diffuse reflectance measurement of the ZnO nanostructures synthesized by the immersion of Zn plates in MB and exposed to UV light for 4 h is shown in Figure 5a.…”

“…Further investigation needs to be done to determine the reason for the lower bandgap; however, it could be due to defects in the ZnO nanostructures [33,34]. The optical bandgap of the ZnO nanostructures was estimated using UV-Vis diffuse reflectance spectroscopy, Kubelka-Munk function (F(R)), and Tauc plot [31,32]. The diffuse reflectance measurement of the ZnO nanostructures synthesized by the immersion of Zn plates in MB and exposed to UV light for 4 h is shown in Figure 5a.…”

High dielectric-energy storage and ferromagnetic-superparamagnetic properties: tetra-doping CuO nanocompositions

“…Copper oxide (CuO) structure is an interesting p-type semiconductor material with remarkable electrical, magnetic, optical and thermal characteristics as well as inexpensive and nontoxic [34]. CuO semiconductor is technologically well-known material having multifunctional properties with promising applications in magnetic storage media [35], gas sensor [36], optical devices [37], catalysts [38], lithium-ion batteries [39], p-n diode [40], solar energy [41] and superconductors [42]. The physical electrical, dielectric, magnetic and optical properties of CuO can be controlled or enriched through incorporation of appropriate dopants into its lattice.…”

Synthesis of Metal (Ni) Doped Metal Oxide (ZnO) Heteronanostructures and Investigation of Their Morphological-Optical Properties

“…In technological applications, metal oxide semiconductor nanoparticles are used for corrosion passivation of surfaces used in manufacturing in solar cells, sensors, microelectronic circuits, fuel cells, piezoelectric devices, coatings and catalysts. Metal oxides such as ZnO, TiO2, NiO, CuO are often used for the mentioned applications [2], [3].…”