Structural and optoelectronic properties of glucose capped Al and Cu doped ZnO nanostructures

Abstract

Al and Cu doped ZnO nanoparticles are considered as appropriate for modulation of structural and optoelectronic properties. Al atoms are found to substitute the host Zn whereas Cu dopants mainly segregate in grain boundaries and thereby determine the optical properties. The undoped as well as Al and Cu doped ZnO exhibit spherical well defined particles. The spherical nanoparticles change to rod type structures on co-doping. The average particle size decreases on doping what consequently results in an increment in band gap. Blue shift in UV absorption is governed by the functional group of glucose; further blue shift occurring on metal doping may be attributed to Burstein-Moss effect. PL spectra of doped and undoped ZnO show a dominant near band gap UV emission along with visible emission owing to the defects. The PL peak intensity increases on doping with Cu and Al. The linear I-V characteristics indicate the ohmic behavior of ZnO nanostructures.

Structural, FTIR spectra and optical properties of pure and co-doped Zn1-x-yFexMyO ceramics with (M = Cu, Ni) for plastic deformation and optoelectronic applications

“…Based on the above results, it is approved that co-doping of (Fe + M) up to 0.30 is well dissolved into the crystalline lattice of ZnO. During sintering at high temperature, the clusters of (Fe + Cu) samples may behave deep donors, and therefore the density of the intrinsic donors is reduced [ 89 , 90 ]. Furthermore, the higher valence state of the co-doping (Fe 3+ /Cu 2+/3 ) compared to divalent Zn 2+ leads to more deep acceptor levels which trap the electrons from the conduction band and then widening the energy gap as obtained.…”

ZnO/Graphene Composite from Solvent-Exfoliated Few-Layer Graphene Nanosheets for Photocatalytic Dye Degradation under Sunlight Irradiation

“…The recombination of electrons from the conduction band to the oxygen interstitial (Oi) energy level is responsible for the prominent wide emission peak at 415 nm. The blue emission peaks at 451 and 468 nm are due to the electron transition between the conduction band minimum and Zn vacancy sites (V zn ), and the transition between the zinc interstitials and valence band maximum [ 56 , 57 ]. The weak shoulder peaks at 482 and 493 nm may be attributed to the oxygen vacancies (V o ) and free excitons (FX) that existed in the ZnO crystal lattice of the composite [ 58 ].…”

Study on the Defect Structure of Carbon‐Doped ZnO Materials

“…It is deduced that the doping of carbon may cause the change of the defect concentration in ZnO, which leads to the decrease of the optical band gap value of the samples. [16] Although the conclusion analysis of the optical band gap energy value is an important part of studying the structure of ZnO, it is necessary to further explore the effect of carbon-doped ZnO on its defect structure from the characterization of Raman spectroscopy and fluorescence. [17] Raman's measurement analyzes the matter from the microscopic perspective, which is equivalent to the transition of the molecule to an intermediate state after absorbing the photons and the spontaneous scattering of the photons from the intermediate state, to further characterize the changes of crystal mass, lattice structure, and defect state.…”

“…It is deduced that the doping of carbon may cause the change of the defect concentration in ZnO, which leads to the decrease of the optical band gap value of the samples. [ 16 ] Although the conclusion analysis of the optical band gap energy value is an important part of studying the structure of ZnO, it is necessary to further explore the effect of carbon‐doped ZnO on its defect structure from the characterization of Raman spectroscopy and fluorescence. [ 17 ]…”