Hexagonal Wurtzite Structure Of ZnO Research Articles

Combustion synthesis of Ce/Mg co-doped ZnO nanoparticles as a visible-light-driven photocatalyst

ZnO and Ce/Mg co-doped ZnO nanoparticles as a visible-light-driven photocatalyst were synthesized by combustion method. X-ray diffraction (XRD) patterns of ZnO and Ce/Mg co-doped ZnO samples were indexed to the pure phase of hexagonal wurtzite ZnO structure without impurity detection. The Raman analysis of ZnO and Ce/Mg co-doped ZnO samples showed optical phonon E2H, A1(TO), E2L, E2H–E2L, A1(LO) and E1(LO) modes of wurtzite ZnO structure, including the detection of Zn−O stretching mode containing in FTIR spectra of hexagonal wurtzite ZnO. Transmission electron microscopic (TEM) images of ZnO and Ce/Mg co-doped ZnO samples showed uniform and good distribution of nanoparticles with different orientations. The photocatalysis of ZnO and Ce/Mg co-doped ZnO nanoparticles was studied through the degradation of methylene blue (MB) illuminated by visible radiation. In this research, the Zn0.97Ce0.015Mg0.015O nanoparticles have the highest efficiency of 95.16% within 150 min because of the largest specific surface area, smallest crystallite size and highest absorption capacity of visible light for active species production in degrading of MB under visible light. Photocatalytic mechanism of Ce/Mg co-doped ZnO nanoparticles in degrading MB was also proposed.

Therapeutic Potential of Sol-Gel ZnO Nanocrystals: Anticancer, Antioxidant, and Antimicrobial Tri-Action.

Zinc oxide nanocrystals (ZnO NCs) hold great promise in nanomedicine with fascinating multifunctional properties. We investigated the therapeutic potential of sol-gel synthesized ZnO NCs with crystal sizes of 52.65 and 25.11 nm, focusing on their anticancer effects on HepG2 and HT29 cells, antioxidant properties, and antimicrobial activity. Both samples displayed a hexagonal wurtzite ZnO structure, wherein the crystal sizes diminished with lower calcination temperatures according to X-ray diffraction. The scanning electron microscopy analysis revealed that lowering the calcination temperature resulted in a decrease in the grain size of the ZnO NCs, as expected. This reduction in grain size combined with a decrease in crystal size resulted in a significant 40% reduction in the reflectance of the ZnO NCs in UV-vis-NIR spectroscopy. It was also observed that the ZnO NCs calcined at higher temperatures exhibited larger particle sizes with a reduced surface area mean of 69.30 μm and a stable negative zeta potential of -11.2 mV. In contrast, the ZnO NCs calcined at lower temperatures exhibited a larger surface area mean of 34.56 μm and a positive zeta potential of +10 mV. In both cell lines, the cytotoxic potential was found to be higher in HepG2 cells. Specifically, when ZnO nanocrystals (NCs) with a crystal size of 52.65 nm were used, the lowest cell viability was observed at a concentration of 5.74 μg/mL. Based on oxidative stress index values, a lower crystal size of ZnO NCs displayed greater effectiveness in HT29 cells, while a higher crystal size of ZnO NCs had pronounced effects in HepG2 cells. Moreover, both ZnO NCs exhibited significant antimicrobial activity against Gram-positive bacteria (Enterococcus faecalis and Staphylococcus aureus) and Candida parapsilopsis fungus. These findings emphasize sol-gel ZnO NCs' potential as versatile agents in nanomedicine, spurring research on targeted cancer therapies and antimicrobial innovations.

Characterization of Ce3+ and Eu3+ doped and co-doped ZnO nanoparticles for luminescence applications

This paper investigates the synthesis of Ce3+ and Eu3+ doped, as well as co-doped ZnO nanoparticles using the solution combustion route. The nanoparticles exhibit a hexagonal wurtzite structure of ZnO with crystallite sizes ranging from 19 to 22 nm. Structural parameters, including lattice constants, bond lengths, and bond angles, are evaluated. Morphological diversity is observed in field-emission scanning electron microscopy images. The diffuse reflectance spectroscopy results reveal an energy band gap of 3.20 eV for undoped ZnO nanoparticles. The energy band gap value slightly decreases for Eu-doped ZnO and certain (Ce, Eu) co-doped ZnO nanoparticles. Photoluminescence (PL) excitation peaks are attributed to energy levels of native defects in the ZnO band gap, along with f–d and f–f transitions of rare-earth ions (Ce3+, Eu3+). The PL emission spectra under different excitation wavelengths (350 nm, 394 nm, and 465 nm) display varied peak positions. ZnO co-doped with 0.96 mol% of Ce3+ and 0.92 mol% of Eu3+ emerges as a promising material for luminescence applications, exhibiting a significant increase in green emission intensity. Consequently, this study represents a novel contribution to the field of ZnO-based luminescent materials.

Synthesis, characterization and properties of Cr-doped ZnO nanoparticles via a facile solvothermal route

Cr-doped ZnO ([Formula: see text]–0.08) nanoparticles are synthesized using the microwave solvothermal irradiation technique. The final product is calcinated at 450∘C and the nanostructure of the material is investigated using various techniques. In structural studies, XRD analysis shows that the hexagonal wurtzite structure of ZnO is present in the standard JCPDS card. FESEM spectrum reveals the hexagonal shape of the synthesized samples and EDS provides information on the qualitative composition of the nanoparticles. Optical absorbance images show exciton peaks in the UV region, which can be attributed to Cr incorporation into the ZnO lattice, and the optical energy bandgap values are calculated using the tauc plot method. Photoluminescence (PL) emission spectra are measured using PL spectroscopy. Interestingly, vibrating sample magnetometry (VSM) reveals enhancements in the magnetic properties in M–H loops and it is widely used for biological applications like antibacterial activity.

Detailed investigation of the structural and electrical properties of ZnO/Fe3O4 nanocomposites

The nanocomposites with the formula (1-x)ZnO+xFe3O4 (x = 0, 0.01, 0.03, 0.05, 0.7 and 0.09) were prepared using the sonomechanical method, while the pristine ZnO and Fe3O4 were prepared using the co-precipitation technique. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and a high-resolution broadband impedance analyzer were used to examine the structural, microstructure, and dielectric properties of the investigated samples. XRD analysis assures the wurtzite hexagonal structure of ZnO for all nanocomposite samples. The FTIR showed the existence of a functional group of ZnO and Fe3O4. The ac conductivity, dielectric constant (ε′), dielectric loss (ε′), electric modulus, impedance, and Nyquist plot were studied as a function of frequency and at different temperatures. The results show that the small concentration of Fe3O4 affects the ac conductivity and dielectric properties. The Koops phenomenological theory and the Maxwell-Wagner interfacial model were used to analyze the observed dielectric dispersion. The analysis of modulus and impedance results indicated the existence of non-Debye relaxation and the involvement of both grains and grain borders in polarization. The impedance study reveals that just one semicircle is observed in all samples, indicating that the influence of grain boundaries is more significant than the contribution of grains.

Enhanced Magnetic Properties of Gd-Doped ZnO by Varying the Gd Concentration via Co-Sputtering Technique

This study reports on the effect of Gd concentrations on the properties of Gd-doped ZnO films. The films were prepared using co-sputtering method at room temperature. Characterization tools such as X-ray diffraction (XRD), atomic force microscopy (AFM), and vibrating sample magnetometer (VSM) were used to analyze the properties of the prepared films. XRD results observed that all the films are well crystalline and designated to the hexagonal wurtzite structure of ZnO with no secondary phases, which confirmed the successful of doping the Gd into ZnO. Topography analysis from AFM discovered the increase of Gd concentrations of Gd-doped ZnO films leads to the increase in grain size and rougher surface of the films. The magnetization of the films effectively depends on the Gd concentrations, which the diamagnetic behavior changed to ferromagnetic behavior upon Gd doping. A film with higher Gd doping concentration is more effective than lower Gd doping in terms of saturation magnetization (Ms), coercivity (Hc) and remanent magnetization (Mr). These findings revealed that optimizing the Gd concentration is very crucial in enhancing the magnetic properties of Gd-doped ZnO films.

Dielectric Barrier Discharge Plasma Processing and Sr-Doped ZnO/CNT Photocatalyst Decoration of Cotton Fabrics for Self-Cleaning Application.

Nonthermal plasma processing is a chemical-free and environmentally friendly technique to enhance the self-cleaning activity of nanoparticle-coated cotton fabrics. In this research, Sr-doped ZnO/carbon nanotube (CNT) photocatalysts, namely, S10ZC2, S15ZC2, and S20ZC2 with different Sr doping concentrations, were synthesized using the sol-gel method and coated on plasma-functionalized fabric to perform the self-cleaning tests. The fabrics were treated with dielectric barrier discharge plasma in an open environment for 3 min to achieve a stable coating of nanoparticles. The energy band gap of the photocatalyst decreased with an increase in the level of Sr doping. The band gap of S10ZC2, S15ZC2, and S20ZC2 photocatalysts was estimated to be 2.85, 2.78, and 2.5 eV, respectively. The hexagonal wurtzite structure of ZnO was observed on the fabric surface composited with CNTs and Sr. The S20ZC2 photocatalyst showed better homogeneity and photocatalytic response on the fabric when compared with S10ZC2- and S15ZC2-coated fabrics. The S20ZC2 photocatalyst showed 89% dye degradation efficiency after 4 h of light exposure in methylene blue solution, followed by S15ZC2 (84%) and S10ZC2 (80%) photocatalysts.

Combustion synthesis and characterization of visible-light-driven La/Al co-doped ZnO nanoparticles used for wastewater treatment

Visible-light-driven LaxAl0.03-xZn0.97O (x = 0.01, 0.015 and 0.02) nanoparticles were synthesized by tartaric acid-assisted combustion method. Both ZnO and La/Al co-doped ZnO samples were indexed to the pure hexagonal wurtzite ZnO structure and were composed of nanoparticles with particle size ranges of 100-150 nm and 20-50 nm, respectively. The photocatalytic activities of ZnO and LaxAl0.03-xZn0.97O (x = 0.01, 0.015 and 0.02) nanoparticles were monitored through the degradation of methylene blue (MB) under visible light irradiation. The La0.02Al0.01Zn0.97O nanoparticles have the highest photocatalytic activity in degrading of MB under visible light irradiation because the La/Al co-dopant played the role in creating shallow energy level under the conduction band of ZnO.

Synthesis of Pure and Manganese Doped Zinc Oxide Nanoparticles by a Solution Growth Technique: Structural and Optical Investigation

Pure and manganese doped zinc oxide nanoparticles have been successfully synthesized over the composition range, Zn1-xMnxO (0<x<0.5), by a solution growth process. The effect of Mn doping on the structure, morphology and optical properties were investigated by several techniques. X-Ray diffraction studies confirmed the formation of a single-phase polycrystalline hexagonal wurtzite structure of ZnO within the range, 0 < x < 0.3. No Mn related secondary phases were detected, within this range, which could be attributed to the fact that the dopant atoms had been well incorporated into the ZnO crystal lattice. For Zn1-xMnxO (x = 0.5), several low intensity peaks belonging to remnants of Manganese acetate were observed in the diffractogram, establishing a solubility limit for the synthesis technique used.  The variation of d-spacing with Mn percent doping showed a very good agreement with Vergard’s law within the range (0<x<0.25). EDAX analysis of the nanoparticles was consistent with the formation of Mn doped ZnO. The optical band gap of the ZnO nanoparticles decreased linearly with increasing Mn percent doping, suggesting the possibility of tuning the band gap of ZnO by doping with Mn.

CeO2-ZnO nano composites: Dual-functionality for enhanced photocatalysis and biomedical applications

In present study, we employed a simple and cost-effective chemical precipitation method to synthesize CeO2:ZnO nanocomposites with various Ce:Zn molar ratios. The X-ray diffraction pattern confirms the formation of a cubic structure of CeO2 and a hexagonal wurtzite structure of ZnO in the Ce:Zn nanocomposites. Structural parameters were determined through a Rietveld refinement process using the X-ray diffraction pattern. The elemental composition of the synthesized compounds were assessed using energy-dispersive X-ray spectroscopy (EDX). Raman spectroscopy revealed the presence of the F2g vibrational mode corresponding to CeO2 NPs as well as the E2 mode corresponding to ZnO NPs. Transmission electron microscopy shows the lateral dimensions of both CeO2 and ZnO nanoparticles in the prepared composites. Photoluminescence (PL) spectra were analysed to examine the defects present in the samples. Absorption spectra were recorded in the wavelength range of 325–1100 nm using UV–Vis spectroscopy. The photocatalytic activity of the synthesized samples was studied for the degradation of methylene blue (MB) under UV light irradiation. Among all prepared composites, the Ce: Zn (1:3) nanocomposite showed the highest photodegradation activity (95 %) against the methylene blue (MB) dye. We also examined in detail the anticancer potential of the Ce:Zn composites against human lung carcinoma cells (A549).

Optical, photo catalytic, electrochemical and antibacterial performance of ZnO and Co doped ZnO nanoparticles

The present work designates the preparation of pure ZnO and Cobalt doped ZnO nanoparticle with the general formula Zn1-xCoxO (x = 0.00, 0.01, 0.03, 0.05) by wet Chemical Co-precipitation technique. The prepared nanoparticles were characterized by XRD, FTIR, SEM with EDAX, UV-DRS and Photoluminescence spectroscopy. XRD outcomes confirmed that these nanoparticles exhibited hexagonal wurtzite structure of ZnO lacking any secondary phase. The crystallite size of the formed products was calculated by Scherrer’s formula. The calculated average crystallite size decreased from 10 to 28 nm (x = 0.00 to 0.05). Through SEM analysis the shape and morphology of the sample was determined, which showed wurtzite structures with irregular dimensions. UV–Vis DRS spectral studies indicated a decrease in the band gap with an increase in doping concentration. Photoluminescence studies exhibited a green emission peak at 521 nm. Additionally, photodegradation of these nanoparticles was evaluated through degradation of MB dye. Synthesized nanoparticles illustrates appreciable electrochemical performance, pH shows nearest to Nernst value, MCPE is adsorption controlled and LOD of PA is very low compared to another modified electrode. Pure ZnO and Co-ZnO were examined against gram-positive Enterococcus faecalis and gram-negative Escherichia coli bacteria and it was found that the anti-bacterial activity improved with Cobalt doping compared to the pure ZnO nanoparticles.

ZnO-based heterojunction catalysts for the photocatalytic degradation of methyl orange dye

In this study, a variety of ZnO-based heterojunctions with disparate wt.% doping of WO3 and BiOI have been prepared for the photodestruction of methyl orange (MO) dye in aqueous solution. The composites were analysed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, optical studies, and nitrogen adsorption-desorption isotherms. The SEM images revealed non-uniform surfaces of the ZnO–BiOI based composites while mostly nodular morphology was observed for all three samples of ZnO-WO3. As the WO3 loading increased, more clustering was detected. The analysed samples exhibited characteristic peaks representative of the triclinic phase of WO3 and the hexagonal wurtzite structure of ZnO, while the diffractogram observed from the materials displayed distinct peaks corresponding to the crystalline phases of both BiOI and ZnO in their pure forms. Further evidence of the samples' characteristics includes the presence of distinct crystalline patterns without any impurity peaks, a red shift in the absorption spectra of the heterostructure, the detection of only the reference elements, and mostly Type IV isotherm adsorption. This study identified the ZnO-[10%]BiOI and ZnO-[10%]WO3 heterojunctions as the best performing photocatalysts, as MO was completely destroyed in 120 and 90 min, respectively. Thus, confirming 10% wt. as the optimal doping concentration for the best photo-activity in this study. The impact of varying process parameters demonstrates that at an elevated photocatalyst mass of 40 mg, both heterojunctions effectively degraded MO. The photodegradation efficiency of MO was more pronounced in strong acidic conditions (pH 2) when compared to high alkaline conditions (pH 11) for the ZnO-[10%]BiOI heterostructure. However, a decrease in performance was observed for both strong acidic and high alkaline pH values when the ZnO-[10%]WO3 heterostructure was applied. The kinetic analysis of the photodegradation study reveals that all the photodegradation experiments can be represented by the pseudo-first-order kinetic model. The findings from this investigation propose that the ZnO-[10%]BiOI heterojunction photocatalyst holds significant potential for the effective treatment of dye-contaminated wastewater.

Optical and structural investigation of methylammonium lead perovskite mixed halide (I, Br, and Cl) on spin-coated zinc oxide

This study investigated the effect of mixing different halides bromine (Br) with iodine (I) and Br with chlorine (Cl) and using only bromide for methylammonium lead perovskites films deposited in ZnO to produce different heterojunctions ZnO/MAPbBr3, ZnO/MAPbBr2I and ZnO/MAPbBr2Cl. Thus, these three heterojunction samples were produced and characterized. The perovskite is deposited at ZnO films showed two main peaks located at 2θ = 33.66° and 2θ = 37.69°. These peaks correspond to the (002) and (101) planes of the hexagonal wurtzite structure of ZnO respectively. The XRD results indicate that all the heterojunction samples show two main peaks at 2θ = 14.79° and 2θ = 29.83° for the (100) and (200) crystallographic planes respectively. The peaks of the sample mixed with iodine are the most intense and those of the sample mixed with chlorine are the least intense. These results also reveal that the mixed samples have lower crystallinity than the unmixed ZnO/MAPbBr3 sample. The SEM results confirmed this. The UV–Visible results indicate that the sample mixed with iodine absorbs the most and has the smallest band gap of 2.15 eV. The band gaps of the heterojunctions range from 2.15 eV to 2.4 eV. The unmixed sample (ZnO/MAPbBr3) has the largest band gap. The degradation study showed that the sample mixed with iodine degrades faster.

Enhancement in photocatalytic activity and biological properties of Sm doped ZnO nanostructures by the increase in Sm contents

The impact of Sm on the photocatalytic and biological properties of ZnO was explored in this study. The sol–gel approach was used to produce undoped and Sm-doped ZnO nanostructures by using Sm 6–10 wt%. The functional groups that appeared in the prepared nanostructures were identified by FTIR. Sm-doped ZnO exhibited a hexagonal wurtzite ZnO structure and Sm ions were successfully embedded into the ZnO matrix. The size of the crystallites was enhanced as the Sm content was increased, pointing to potential applications in photocatalysis and biological science. These nanocrystals were expected to break down bacterial and chemical pollutants in water when exposed to visible sunshinewavelengths. 9 wt% Sm in ZnO had shown the best photocatalytic performance. The effects of Sm concentration on antibacterial activity against Escherichia coli (E. coli), Pseudomonas aeruginosa (K. Pneumonia) and Staphylococcus aureus (S. aureus) were probed in this research through agar well diffusion method. Sm doped ZnO nanostructures were effective against all selected bacterial strains. The development of sensors, photovoltaic panels, wastewater treatment and water-splitting applications are the few applications of Sm-doped ZnO.

Eco-Friendly Green Synthesis and Photocatalyst Activity of Ag-ZnO Nanocomposite

The study successfully synthesized Ag NPs, ZnO NPs, and Ag/ZnO nanocomposites using an easy, cost effect and sustainable green synthetic approach. The purpose of synthesizing Ag/ZnO nanocomposites using two different plant extracts was to study their photo-degradation activity on Methylene Blue (MB) dye. (XRD) diffraction analysis confirmed the presence of Ag crystalline size and the wurtzite hexagonal structure of ZnO. (FE-SEM) results indicated spherical, nanorods and there is Clustering of NPs with an irregular shape. The resulting metal/semiconductor oxide nanocomposites possessed unique photo degradation characteristics that were absent in the individual Ag NPs and ZnO NPs.
  

Optical Properties of Heterostructured ZnO/NiO Nanocomposites Synthesized via Facile Precipitation Process

The semiconductor zinc oxide/nickel oxide (ZnO/NiO) heterostructured nanocomposites have been successfully synthesized via facile and eco-friendly homogeneous precipitation process with ethanol and water as solvents. The prepared nanocomposites were studied by means of structural and optical characteristics by using X-ray diffraction, ultraviolet visible absorption and photoluminescence  emission spectro-scopies. The peaks in the XRD pattern attributed to the hexagonal wurtzite structure of ZnO and face-centered cubic  structure of NiO, as a result the XRD analysis further confirmed that the solvents play a powerful role in size of the crystallite of the  synthesized nanocomposites. Strong UV absorption may be seen in UV-vis absorbance spectra and samples of ZnO/NiO  nanocomposite materials had greater energy gap (Eg) values than those of pure NiO and ZnO materials. The synthesized materials  have demonstrated high photoluminescence emission in UV-blue region in the range of 241-498 nm, it might be a valuable source for  future display applications. According to the aforementioned finding, the ZnO/NiO nanocomposites showed significant promise and  were a viable material for optoelectronic devices. 

Au nanoparticles dispersed chitosan/ZnO ternary nanocomposite as a highly efficient and reusable visible light photocatalyst

The environmental pollution in particular contamination of surrounding and ground water are major concerns for regulation authorities and scientific community. In the current work, a novel visible light ternary photocatalytic structure based on mesoporous ZnO in combination with chitosan (CSN) and gold nanoparticles (AuNPs) was synthesized for serious water pollution issue. The Au@CSN/ZnO nanocomposite photocatalyst was developed through the sol-gel methodology followed by ultrasonication and photoreduction techniques. XRD investigation revealed the hexagonal wurtzite structure of ZnO, while XPS and FTIR measurements confirmed the formation of ternary nanocomposite among Au, CSN and ZnO. TEM analysis revealed the presence of AuNPs (5–15 nm), CSN sheets (micron size) and ZnO nanoparticles (20–120 nm) in designed ternary photocatalyst. Diffuse reflectance spectroscopy showed lowering in band gap energy from 3.1 to 2.87 eV as bare ZnO modified to Au@CSN/ZnO. The as-fabricated Au@CSN/ZnO nanocomposite was proven as a decidedly efficient photocatalyst when employed on colorless insecticide imidacloprid (IMD) and on colored methylene blue (MB) dye under visible-light illumination. Efficient photocatalytic performance with 93.21% removal of insecticide only in 20 min was achieved, representing 211% more efficient than bare mesoporous ZnO. In addition, Au@CSN/ZnO nanostructure showed rapid removal of MB with almost complete destruction of complicated structure just in 12 min under visible light. Furthermore, the current-developed photocatalyst exhibited adequate stability and recyclability, which is beneficial for the practical application in environmental remediation.

Study of the Influence of Doping on the Structural, Optical and Electrical Properties of zinc oxide thin Films Produced by by Spray Pyrolysis for Solar Cell Applications

In the present study, the effect of Al doping with 0.5 % Al (AZO-0.50), 1 % Al (AZO-1.00), and 1.5 % Al (AZO-1.50) have been successfully synthesized by Spray Pyrolysis method. The structural, optical and electrical properties of the obtained films was studied. The obtained films are characterized by different techniques such as X-ray diffraction (XRD), UV-visible and electrical Hall Effect measurements. The X-ray diffraction confirmed that the Al doping did not change the ZnO Hexagonal Wurtzite structure. Spectroscopic measurements in the UV-VIS-IR wavelength range were found to give good average transmittance values of about 73%, with a high transmittance of 75% with 0.5% Al doping. The optical gap value increases in the range of 3.23 to 3.26 eV with increasing aluminium content. The electrical analysis shows that the conductivity improved with doping compared to the pure ZnO film

Enhancement of thermoelectric properties of transition metals, nickel and copper dually doped ZnO

Thermoelectricity is one of the potential sustainable energy sources, that can be treated as a remedy for the present energy scarcity as it is a clean-green technology. ZnO is a promising multifunctional metal oxide and its thermoelectric conversion property is highly exploited in the field of waste heat recovery. Herein, the impact of nickel and copper substitution on the thermoelectric properties of ZnO is investigated. The structural and morphological analysis of the doped materials confirmed the hexagonal wurtzite structure of ZnO. The strain induced in the lattice and the variation of crystallite size established the substitution of the dopants into the host matrix. The optical band gap energy shows a reduction from 3.1 eV to 2.15 eV with a redshift in the absorption edge. The electrical conductivity and Seebeck coefficient of ZnO increased upon doping. The most remarkable result of nickel and copper doping is the enhancement of the Seebeck coefficient to 1318 µV/K. As a result of the lattice distortion created due to the dual substitution of the dopants, the thermal conductivity is considerably reduced to 8.36 W/mK. The power factor enhancement and degradation of thermal conductivity give rise to a six-fold increase in the thermoelectric figure of merit of the material.

Solution combustion synthesis of Dy-doped ZnO nanoparticles: An investigation of their structural, optical and photoluminescence characteristics

Undoped and Dy-doped ZnO nanoparticles were synthesized by solution combustion technique using urea as fuel. The synthesized nanoparticles were examined by various characterization tools for their structural, optical and photoluminescence properties. All the nanoparticles are found to possess the hexagonal wurtzite structure of ZnO with crystallite sizes in the range of 16–23 nm. The structural parameters viz. lattice constants, bond lengths, bond angles, and lattice strain of the nanoparticles have been evaluated. The high-resolution transmission electron micrographs and selected area electron diffraction patterns confirm the high crystallinity of the nanoparticles. The optical bandgap estimated from the diffuse reflectance spectra using the Kubelka-Munk method is found to be 2.90 eV for the undoped ZnO. A sharp narrow UV emission peak at ∼396 nm originating from the excitonic recombination is observed in the PL spectra of all the nanoparticles. The visible emission peaks in the PL spectra of undoped ZnO are attributed to different native defects, whereas in Dy-doped ZnO nanoparticles, the visible emissions (blue, yellow and red) are assigned to the 4f intrashell transitions in Dy3+ ions. It has been concluded that the solution combustion synthesized 5 mol% Dy-doped ZnO can be a promising material for white luminescence applications.