Investigations on structural, optical and electrical property of ZnO-CuO core–shell nano-composite

Kanani, Maryam; Dhruv, Davit; Rathod, H.K.; Rathod, K.N.; Rajyaguru, Bhargav; Joshi, A.D.; Solanki, P.S.; Shah, N.A.; Pandya, D.D.

doi:10.1016/j.scriptamat.2019.01.027

Cited by 23 publications

(8 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4 f), where F(R) is the Kubelka–Munk function, with F(R) = (1 − R) 2 /2R and R the measured diffuse reflectance, the band gap value was estimated at ~ 1.5 ± 0.1 eV. The band gap values are consistent with those previously reported for CuO nanowires 51 and CuO–ZnO core–shell heterostructures 52 .…”

Section: Resultssupporting

confidence: 88%

Photodetecting properties of single CuO–ZnO core–shell nanowires with p–n radial heterojunction

Costas

Florica

Preda

et al. 2020

Sci Rep

View full text Add to dashboard Cite

CuO–ZnO core–shell radial heterojunction nanowire arrays were obtained by a simple route which implies two cost-effective methods: thermal oxidation in air for preparing CuO nanowire arrays, acting as a p-type core and RF magnetron sputtering for coating the surface of the CuO nanowires with a ZnO thin film, acting as a n-type shell. The morphological, structural, optical and compositional properties of the CuO–ZnO core–shell nanowire arrays were investigated. In order to analyse the electrical and photoelectrical properties of the metal oxide nanowires, single CuO and CuO–ZnO core–shell nanowires were contacted by employing electron beam lithography (EBL) and focused ion beam induced deposition (FIBID). The photoelectrical properties emphasize that the p–n radial heterojunction diodes based on single CuO–ZnO core–shell nanowires behave as photodetectors, evidencing a time-depending photoresponse under illumination at 520 nm and 405 nm wavelengths. The performance of the photodetector device was evaluated by assessing its key parameters: responsivity, external quantum efficiency and detectivity. The results highlighted that the obtained CuO–ZnO core–shell nanowires are emerging as potential building blocks for a next generation of photodetector devices.

show abstract

Section: Resultssupporting

confidence: 88%

Photodetecting properties of single CuO–ZnO core–shell nanowires with p–n radial heterojunction

Costas

Florica

Preda

et al. 2020

Sci Rep

View full text Add to dashboard Cite

show abstract

“…Optical properties study of the nanocomposite thin films (Co 3 O 4 :Cr 2 O 3 /C) plays a significant role in understanding the nature of optoelectronics. Nanocomposite thin films properties are interpreted in terms of interference between the incident solar radiation of the semiconducting thin films, and through the study of the band gap energy obtained from optical absorption by demonstrating the band structure of semiconductors . The investigation and discussion of optical (Co 3 O 4 :Cr 2 O 3 /C) nanocomposite thin films depend on measurements of reflectance, R(λ), in the spectral range of 250 to 1300 nm.…”

Section: Resultsmentioning

confidence: 99%

“…Absorbed heat calculation was achieved by subjecting the coated samples to solar energy directly. After measuring the temperature, the absorbed heat can be calculated using the following equation:

Qabs . = mc \frac{∆ T}{∆ t},

where, Q is the heat absorbed (W/m 2 ), m is the mass of the sample (kg), c is the specific heat for Al (J/kg.k), T is the temperature (K), and t is the time (seconds).…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Spectrally selective coating of nanoparticles (Co₃O₄:Cr₂O₃) incorporated in carbon to captivate solar energy

et al. 2020

View full text Add to dashboard Cite

Innovatory nanocomposite comprising nanomaterials Co 3 O 4 :Cr 2 O 3 and carbon (fuel ash) was designed to absorb solar energy. Different concentration ratios of Co 3 O 4 and Cr 2 O 3 nanoparticles were utilized as a dopant for fuel thin films synthesis via spin and casting methods on glass and aluminum substrates. The opticalproperties of the modified films demonstrated in the range of 250 to 1300 nm. The data were interpreted in terms of a phonon-assisted theory. Energy gap (E g ) of doped C was calculated with different concentration ratios of Co 3 O 4 :Cr 2 O 3 (0.5:2.5, 1:2, 1.5:1.5, 2:1, 2.5:0.5) wt%, and fixed concentration of C in 7wt%. The results showed E g of the doped samples in the range of 2.9 to 3.9 eV. In addition, the intensity of the solar radiation was measured. The absorptivity was in the range of 88 to 93.6%. The above results are comparable to those of semiconductors and have high absorptivity values when the nanocomposite was utilized on a flat plate collector as a coating to trap and absorb solar energy. K E Y W O R D S chromium oxide, cobalt oxide, emissivity and absorptivity, energy band gap, optical properties 1 | INTRODUCTIONGenerally, Iraq has 240 days of strong sunlight with energy of 5 kWh per square meter in a day. 1 Harvesting solar energy and utilizing it in domestic applications, such as heating the water or ventilation residential complexes, would be highly cost effective and environment friendly. Nanocomposite films are used for this purpose. The technology includes the use of the nanocomposite films as a coating on a flat plate collector to be spectrally selective surface. This surface has low emissivity and high absorptivity to solar energy to convert this solar light into heat. 1,2 Doping nanomaterials with carbon can cause a remarkable change to its optical properties. [3][4][5] Cobalt oxide (Co 3 O 4 ) is a prevalent factor having several oxidization states because of its unusual chemical and physical features. It is used in ceramics production as an additional factor to produce blue coloring glazes, photo-catalysis, 6-10 and absorbance energy storage. 5,11 Further, Co 3 O 4 does has significant electrical properties. When Co 3 O 4 is added to chromium oxide (Cr 2 O 3 ), a conductive network is created through the pores. 12-15 Among the oxides family, Co 3 O 4 is one of the multilateral oxide sided, it has properties similar to a p-type semiconductor, and the band gap ranges from 2.23 to 3.38 eV. 16,17 Co 3 O 4 has attracted exceptional attention in the domain of application technology for pigments and solar-selective surfaces. [18][19][20] The particle size of Co 3 O 4 for nano-or micro-size provides perfect performance for electrochemical of different ranges in electronic applications and solar energy coating. [21][22][23][24] Nanocrystalline thin films nickel-cobalt oxides (NiO-CoO) were deposited on steel and glass substrates to produce thin films of different concentrations by the chemical bath deposition (CBD) method. These thin films exhibited semiconductor feature...

show abstract

“…Nevertheless, the increase in temperature induced a monotonic increase in the dielectric parameters and can be explained by the boosted mobility of the electrical dipoles within the dielectric medium [43]. Although the solution pH value had no effect on the behavior of dielectric parameters with frequency and temperature, it remarkably affected their magnitude where dielectric constant increased but dielectric loss decreased with the increase in solution pH value [47]. The pH-induced increase in dielectric constant can be interpreted as an increase in capacitance of the lms with the increase in pH value, and the latter can be due to the increase in interaction with hydroxyl ions which shows the role of functional groups as active centers of charge adsorption.…”

Section: Electrical Analysismentioning

confidence: 99%

Critical effect of reaction pH on the microstructural, optical and electrical behavior of ZnO/CuO hetero-structured nanocomposite films

Ajjaq²,

Ateş³

et al. 2022

Preprint

View full text Add to dashboard Cite

CuO nanocomposite films and ZnO/CuO nano-heterostructures were synthesized by a series of chemical reactions at different pH values based on the hydrothermal and SILAR (successive ionic layer adsorption and reaction) methods. The ultimate purpose of this work is to explore the impacts of solution pH value and ZnO-based heterostructure on the structural, optical and electrical features of CuO films using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), transmittance spectrum, current-voltage (I-V) measurements and capacitance-conductance (C-G) measurements in 300–600 K temperature range and 20 Hz–1.5 MHz frequency range. XRD analysis revealed that the crystallite size and strain lattice parameters decrease with the increase in pH value without affecting the crystalline structure of the synthesized films. SEM images revealed the regular growth of ZnO structure without any deterioration in the CuO substrate layer where an increase in the thickness of the formed rods was observed with the increase in reaction pH value. Transmittance dropped greatly with the formation of heterojunction from about 40% (for CuO) to about 1% (for ZnO/CuO) in the visible range followed by a crystallite size-induced change in bandgap from 2.29 eV to 2.32 eV (for CuO) and from 2.03 eV to 2.11 eV (for ZnO/CuO). The increase in pH from 11.0 to 11.2 increased the room-temperature resistance of ZnO/CuO composites from 377 MΩ to 474 MΩ, the ideality factor from 4.41 to 4.68 and the barrier height from 0.74 eV to 0.83 eV. It can be deduced that reaction pH value is an important synthesis parameter that can tune the structural, morphological, optical and electrical properties of ZnO/CuO nanocomposite films for advanced industrial or technological implementations by controlling the nucleation and crystal growth rates during chemical synthesis processes.

show abstract

Investigations on structural, optical and electrical property of ZnO-CuO core–shell nano-composite

Cited by 23 publications

References 31 publications

Photodetecting properties of single CuO–ZnO core–shell nanowires with p–n radial heterojunction

Photodetecting properties of single CuO–ZnO core–shell nanowires with p–n radial heterojunction

Spectrally selective coating of nanoparticles (Co₃O₄:Cr₂O₃) incorporated in carbon to captivate solar energy

Critical effect of reaction pH on the microstructural, optical and electrical behavior of ZnO/CuO hetero-structured nanocomposite films

Contact Info

Product

Resources

About

Investigations on structural, optical and electrical property of ZnO-CuO core–shell nano-composite

Cited by 23 publications

References 31 publications

Photodetecting properties of single CuO–ZnO core–shell nanowires with p–n radial heterojunction

Photodetecting properties of single CuO–ZnO core–shell nanowires with p–n radial heterojunction

Spectrally selective coating of nanoparticles (Co3O4:Cr2O3) incorporated in carbon to captivate solar energy

Critical effect of reaction pH on the microstructural, optical and electrical behavior of ZnO/CuO hetero-structured nanocomposite films

Contact Info

Product

Resources

About

Spectrally selective coating of nanoparticles (Co₃O₄:Cr₂O₃) incorporated in carbon to captivate solar energy