Wurtzite Structure Research Articles

Silicon-integrated scandium-doped aluminum nitride electro-optic modulator

Scandium-doped aluminum nitride (AlScN) with an asymmetric hexagonal wurtzite structure exhibits enhanced second-order nonlinear and piezoelectric properties compared to aluminum nitride (AlN), while maintaining a relatively large bandgap. It provides a promising platform for photonic circuits and facilitates the seamless integration of passive and active functional devices. Here, we present the design, fabrication, and characterization of Al0.904Sc0.096N electro-optic (EO) micro-ring modulators, introducing active functionalities to the chip-scale AlScN platform. These waveguide-integrated EO modulators utilize sputtered Al0.904Sc0.096N thin films as the light-guiding medium, with the entire fabrication process being compatible with complementary metal-oxide-semiconductor (CMOS) technology. We extract the in-device effective EO coefficient of 2.86 pm/V at 12 GHz. The devices show a minimum half-wave voltage-length product of 3.12 V·cm at a modulation frequency of 14 GHz, and achieve a 3-dB modulation bandwidth of approximately 22 GHz. Our work provides a promising modulation scheme for cost-effective silicon-integrated photonics systems.

Highly tunning of dielectric and photocatalytic properties of crystalline ZnO semiconductor: Functionality of Ba additives

Abstract In the present work, the concentration of Ba-additive played a significant role in advancing the dielectric properties and photo-removal activity of ZnO semiconductor for methylene blue dye. Ba doped ZnO semiconductor with different doping concentrations (Zn1-xBaxO, x = 0.003, 0.005, 0.007 and 0.009 wt.%) were grown by solid-state reaction route. The X-ray diffraction (XRD) data confirmed the formation of the wurtzite structure of ZnO along with the presence of BaO-based secondary phase (SP). The XRD peak intensity related to the SP was found to increase with the increase of Ba concentration. Microstructural analyses through scanning electron microscope (SEM) images and energy-dispersive X-ray analysis (EDS) showed that with the addition of Ba, a gradual increase in the grain size was observed. Furthermore, SP segregated at the grain boundary and showed an increasing trend with doping. The emergence of secondary phases with Ba concentration was confirmed with the help of supplementary spectroscopic characterizations including Fourier transform infrared spectroscopy (FTIR) and UV-Vis diffuse reflectance. The presence of BaO secondary phase has shown a benefit effect on the dielectric and photodegradation properties of ZnO material. The remarkable resistance reduction suggested that the higher Ba concentrations significantly enhance charge carrier mobility. For wastewater treatment uses, BZO9 photocatalyst exhibited a perfect degradation efficiency of 90.1% for methylene blue (MB) removal after 210 min of visible light illumination.

Eu3+-doped ZnO quantum dots: structure, vibration characteristics, optical properties, and energy transfer process.

This article studies the synthesis, as well as the structural, vibrational, and optical properties of Eu3+-doped ZnO quantum dots (QDs) and investigates the energy transfer mechanism from the ZnO host to Eu3+ ions using Reisfeld's approximation. Eu3+-doped ZnO QDs at varying concentrations (0-7%) were successfully prepared using a wet chemical method. The successful doping of Eu3+ ions into the ZnO host lattice, as well as the composition and valence states of the elements present in the sample, were confirmed through X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses. XRD results demonstrated the crystalline nature of the ZnO QDs, revealing their wurtzite (WZ) structure with no secondary phases. XPS analysis provided further confirmation of the presence of Eu3+ ions within the ZnO host, with clear signals corresponding to the Zn, O, and Eu elements. The valence states of Eu were verified as trivalent (Eu3+), confirming the successful doping of Eu3+ ions, as evidenced by the characteristic Eu 3d peaks in the XPS spectra. Raman spectroscopy (RS) was employed to analyze the vibrational modes, revealing shifts in ZnO lattice vibrations due to Eu3+ incorporation, indicating strong coupling between Eu3+ ions and the ZnO host. Optical properties were studied using UV-Vis absorption, photoluminescence (PL) spectroscopy, and PL decay spectroscopy, showing a significant enhancement of red emission, attributed to the 5D0 → 7F2 transition of Eu3+ ions under UV excitation. Using Judd-Ofelt (JO) analysis, the intensity parameters (Ω 2, Ω 4, Ω 6) were derived, providing insights into the asymmetry of the Eu3+ ion's local environment and the radiative transition probabilities. Energy transfer processes between the ZnO host and Eu3+ dopants were examined, showing efficient sensitization of Eu3+ through excitation of the ZnO host, with an optimal Eu3+ doping level maximizing luminescence. Eu3+-doped ZnO QDs, which emit in the visible light region and are non-toxic, have great potential for applications in photonic devices, light-emitting diodes, and bioimaging.

High‐Performance Ammonia Sensing with Citrus Hystrix‐Mediated ZnO Nanoparticles in TFT‐Based Devices

Abstract: We present a sustainable green synthesis approach for zinc oxide nanoparticles (ZnO NPs) utilizing Citrus hystrix leaf extract and their application as an active medium in a thin film transistor (TFT)‐based ammonia gas sensor. For the first time, ZnO NPs derived from Citrus hystrix serve as a receptor layer in a thin film transistor (TFT) device, enabling selective ammonia detection at a significantly reduced initiation temperature. The synthesized ZnO NPs, with a wurtzite structure and an average crystallite size of approximately 14 nm, are deposited onto the TFT sensor without the need for an external conducting layer. The sensor demonstrates excellent sensitivity and selectivity, achieving a maximum response of ~85% at 20 ppm, with a rapid response time of about 10 seconds at room temperature. Notably, the TFT device exhibits an electron mobility of ~10.2 cm²/V·s and a high on/off ratio (>10⁴) at room temperature. The sensing mechanism is attributed to the oxidation‐reduction interactions between surface‐adsorbed oxygen and NH₃ molecules on the ZnO NPs, which modulate the device’s electrical conductivity. This work underscores the importance of eco‐friendly fabrication of high‐performance, durable devices, addressing contemporary environmental and economic concerns.

Starch-Assisted Eco-Friendly Synthesis of ZnO Nanoparticles: Enhanced Photocatalytic, Supercapacitive, and UV-Driven Antioxidant Properties with Low Cytotoxic Effects.

This study presents an efficient and environmentally sustainable synthesis of ZnO nanoparticles using a starch-mediated sol-gel approach. This method yields crystalline mesoporous ZnO NPs with a hexagonal wurtzite structure. The synthesized nanoparticles demonstrated remarkable multifunctionality across three critical applications. In photocatalysis, the ZnO NPs exhibited exceptional efficiency, achieving complete degradation of methylene blue within 15 min at pH 11, significantly surpassing the performance of commercial ZnO. Under neutral pH conditions, the nanoparticles effectively degraded various organic dyes, including methylene blue, rhodamine B, and methyl orange, following pseudo-first-order kinetics. The methylene blue degradation process was aligned with the Langmuir-Hinshelwood model, emphasizing their advanced catalytic properties. For supercapacitor applications, the ZnO NPs attained a high specific capacitance of 550 F/g at 1 A/g, underscoring their potential as energy storage solutions. Additionally, the nanoparticles demonstrated strong UV-induced antiradical activity, with an EC50 of 32.2 μg/mL in DPPH assays. Notably, the cytotoxicity evaluation revealed an LC50 of 1648 μg/mL, indicating excellent biocompatibility. This study highlights a sustainable approach for the synthesis of multifunctional ZnO NPs that offers effective solutions for environmental remediation, energy storage, and biomedical applications.

Ferromagnetic behavior of Cr-doped ZnS nanosheets prepared by solvothermal method

ABSTRACT The undoped and Cr doping ZnS nanostructures have been synthesized using the solvothermal methods. X-ray diffraction measurements indicate that undoped and Cr doping ZnS nanosheet exhibit a wurtzite structure. The nanosheets have rule morphologies, with a thickness of approximately 30–80 nm, a width of 150–300 nm, and a length of 170–470 nm. The results of component analysis indicated that the sample contained Cd, S and Cr. The optical characteristic of undoped ZnS nanosheet is investigated using UV-Visible spectroscopy. From the magnetic research, it can be observed that undoped ZnS nanosheet displays diamagnetism at room temperature, while Cr doping ZnS nanosheet displays ferromagnetism. Spontaneous magnetization ( M s ) of Cr doping ZnS nanosheet (Cr = 8.35at%) is roughly 8.961 (10−3emu/g), and coercivity ( H c ) is roughly 90.554Oe. Ferromagnetism of Cr-doping ZnS nanosheet may be induced by the dual exchange mechanism principle.

Kinetics, central composite design and artificial neural network modelling of ciprofloxacin antibiotic photodegradation using fabricated cobalt-doped zinc oxide nanoparticles

Cobalt-doped zinc oxide nanoparticles were fabricated and examined in this study as a potential photocatalyst for the antibiotic ciprofloxacin (CIPF) degradation when exposed to visible LED light. The Co-precipitation technique created Cobalt-doped zinc oxide nanoparticles that were 5, 10, and 15% Co-loaded. Different known techniques have been used to characterize the synthesized ZnO and cobalt-doped ZnO nanoparticles. Compared to ZnO and other Cobalt-doped ZnO nanoparticles, the experiments showed that 10% Cobalt-doped ZnO nanoparticles were a very effective catalyst for CIPF photodegradation. According to XRD, these NPs have a hexagonal Wurtzite structure with an average size of between 38.47 and 48.06 nm. Tauc plot displayed that the optical energy band-gap of ZnO NPs (3.21) slowly declines with Co doping (2.75 eV). The enhanced photocatalytic activity of Cobalt-doped ZnO nanoparticles, which avoids electron-hole recombination, is brought on by the implantation of Co. Within 90 min, a 30 mg/L solution of ciprofloxacin was destroyed (> 99%). The kinetics studies demonstrated that the first-order model, with R2 = 0.9703, is appropriate for illuminating the pace of reaction and quantity of CIPF elimination. The recycled Cobalt-doped zinc oxide nanoparticles enhanced photocatalytic performance toward CIPF for 3 cycles with the same efficiency. Furthermore, optimization of the 10% Cobalt-doped zinc oxide nanoparticles using a Central composite design (CCD) was also studied. The optimal parameters of pH 6.486, 134.39 rpm shaking speed, 54.071 mg catalyst dose, and 31.04 ppm CIPF initial concentration resulted in the highest CIPF degradation efficiency (93.99%). Artificial neural networks (ANN) were used to simulate the experimental data. The backpropagation technique was used to train the networks with 152 input-output patterns. After experimenting with various configurations, the best results with a correlation value (R2) of 0.9780 for data validation were obtained using a three-hidden layered network that included five, five, and eight neurons, respectively.

Photoluminescent, optical and magnetic property characterization of green chemistry method prepared calcium doped ZnO nanoparticles

Employing a green synthesis technique, we produce cost-effective zinc oxide nanoparticles and calcium-doped zinc oxide nanoparticles by utilizing Citrus sinensis fruit extract as an efficient reducer and encapsulating agent. XRD analysis confirmed a wurtzite structure for the as synthesized ZnO and calcium doped ZnO nanoparticles. Oxidation states and quantification of the element on the surfaces of pure and Ca-ZnO was achieved through XPS investigations. Nano-flakes structures of the synthesized samples are prominently depicted in the HR-SEM image, providing visual insight into their morphology. The elemental analysis and their quantity were discerned using EDX spectrum. Moreover, Magnetization– Field (M–H) hysteresis curves demonstrated diamagnetic behavior at room temperature

Effect of substrates on the structural and optical properties of cobalt-doped ZnO thin films

Cobalt-doped zinc oxide (CZO) thin films (Co: 3 at.%) were synthesized on glass and silicon substrates via pulsed laser deposition (PLD) at 450°C. This study investigates the substrate’s influence on the films’ structural, optical, and electrical properties. X-ray diffraction revealed a highly crystalline hexagonal wurtzite structure with a strong (002) orientation, especially on Si(111) substrates. Rutherford backscattering spectrometry confirmed the film’s thickness (305 nm) and composition, while M-lines spectroscopy provided precise refractive index measurements. Optical analysis showed high transparency (65–80% in the visible range) with a bandgap of 3.26 eV. Electrical characterization demonstrated substrate-dependent properties, with carrier mobility reaching 116.70 cm²/V·s on Si-poly substrates. These findings highlight the critical role of substrate choice in optimizing CZO films for optoelectronic applications. Silicon substrates, particularly Si(111), demonstrated superior performance in improving crystalline quality and optical properties, making them ideal for advanced devices. Furthermore, the study underscores the importance of precise deposition techniques to achieve uniformity and desired functional properties. Future research should focus on exploring alternative substrates and advanced deposition conditions to further enhance these thin films' applicability in areas like solar cells, transparent conducting layers, and waveguides.

Theoretical study on structural stability and miscibility of ScAlN alloys: effect of lattice constraint

Abstract The structural stability and miscibility of ScAlN are theoretically investigated on the basis of density functional calculations. The calculations demonstrate that the relative stability between wurtzite and rocksalt structures depends on Sc composition. The lattice constraint of AlN and GaN substrates enhances the stability of wurtzite structure as well as the miscibility of ScAlN alloys. Furthermore, the calculated energy barrier for polarization switching is also influenced by the lattice constraint. The results give insights for understanding the effect of substrate on structural stability and miscibility of ScAlN alloys.

Anchorage of ZnO quantum dots and CuO on graphene for sonophotocatalytic treatment of pharmaceutical effluent: From experimental data and prediction by advanced machine learning algorithms

Quantum dots (QDs) have recently received much attention as photocatalysts due to their unique properties. Despite the advantages reported for QDs as photocatalysts in literature, their sonophotocatalytic/photocatalytic activity is still hindered by a series of barriers, which limit them to operate after several successive cycles efficiently. The main aim of this work is to fabricate an efficient and recyclable sonophotocatalyst/photocatalyst using ZnO quantum dots (ZQDs), tenorite (CuO), and graphene (G). In this regard, different amounts of ZQDs (ZQDs(x)/G, x= 10, 20, 30, 40, and 50mg) were immobilized on graphene by hydrothermal method and various weight percent of CuO was impregnated on ZQDs(40)/G. The PXRD patterns and Raman spectra confirmed the wurtzite and monoclinic crystal structure for ZQDs and CuO, respectively. Also, FESEM, AFM, and PXRD showed that the mean crystal size of ZQDs increased after immobilization on graphene and impregnation by CuO. PL and Mott–Schottky analyses showed that the presence of GO and CuO in CuO(0.5)/ZQDs(40)/G reduced the recombination of excitons and formed p-n heterogeneous junctions between CuO and ZnO. The VB and CB potential and bandgap energy were obtained using DRS and Mott–Schottky analyses, and the mechanism of tetracycline (TC) degradation was proposed according to active species trapping and H2O2 paper testes. The apparent rate constant (kapp) was 0.030 and 0.060min-1 for photocatalytic and sonophotocatalytic degradation of TC in the presence of CuO(0.5)/ZQDs(40)/G, respectively. The treated effluent of TC showed acceptable performance in growing wheat seeds. The electricity cost estimation showed that (CuO(0.5)/ZQDs(40)/G) consumed less electricity in sonophotocatalytic/photocatalytic TC degradation and could also be used in several successive cycles. Finally, two RF and AdaBoost models based on ML algorithms were developed to predict photocatalytic/sonophotocatalytic degradation. The results showed that the values of statistical metrics, including SAE, MAE, MSE, and RMSE, for the AdaBoost model were relatively lower than those for the RF model, indicating better prediction performance in train and test datasets.

STRUCTURAL RESEARCH OF LI DOPED ZNO POWDERS

In this article, a series of Li-doped ZnO powders was prepared by melt growth from salt mixtures and investigated by means of Mass-Spectrometry (MS), Scanning Electron Microscopy (SEM), Powder X-Ray Diffraction (PXRD), Raman, Photoluminescence (PL) and Nuclear Magnetic Resonance (NMR) spectroscopies. The MS found that the Li concentration fell into the range from 0.87 to 3.31 atomic % for the prepared Li-doped powders. The powders constituted of slightly elongated particles, covering broad range from hundred nanometres to couple micrometres, as shown by SEM. The PXRD showed that the particles of all powders crystallized in the wurtzite (ZnO) structure with no impurities. The Rietveld analysis found that Li occupied octahedral interstitial positions in the ZnO lattice, together with the contraction of the lattice parameters a and c by 0.09 % and 0.13 %, respectively, upon doping with 1 % of Li ions. The Raman spectra exhibited A1(LO) and E1(LO) peaks absent in the undoped sample, supporting the Li incorporation into the ZnO lattice. The PL spectra of Li-doped samples exhibited a visible (~2.15 eV) and near infrared (~1.63 eV) luminescent bands associated with intrinsic defects and Li-Li nanoclusters, respectively. The presence of octahedral Li site along with multiple scattered Li sites was proved with almost zero electric field gradient (EFG) originating from octahedral voids in the wurtzite and various non-zero EFG in course of NMR measurement. Finally, the conducted structural research confirmed incorporation of Li into octahedral interstitials of the ZnO lattice supporting possible formation of Li-Li nanoclusters luminescent in the near infrared range.

The effect of interface polarity on the basal dislocations at the GaN/AlN interface.

The unavoidable high-density dislocations in GaN usually hinder the normal operation of GaN-based devices. The current theoretical research studies mainly focus on threading dislocations in the bulk GaN crystal. Here, we alternatively turn our attention to the basal dislocations, which have been directly observed in experiments but have been less studied. The results from the density-functional theory and empirical molecular dynamic calculations indicate that the Al-polar GaN/AlN interface is more conductive to the formation of Shockley partial dislocations, which are the main dislocations formed during the early growth of GaN on AlN and the precursor of the threading edge dislocations. The dislocation density and local geometry in GaN deposited on AlN strongly depend on the temperature. Overall, choosing N-polar AlN as a substrate for GaN growth at 1900 K helps to obtain high-quality GaN with a greater wurtzite structure content and fewer dislocations.

Biogenesis of Copper Oxide Nanoparticles using Marine Bacteria Pseudomonas aeruginosa: In vitro Antimicrobial and Photocatalytic Activities

The current study outlines an environmentally friendly procedure to synthesis the extracellular secondary metabolite-mediated copper oxide nanoparticles (CuONPs) using Bioinspired green chemistry method with Pseudomonas aeruginosa isolated from a marine water sample. The in vitro bio-reduction of Copper sulphate to CuONPs in the presence of secondary metabolites was confirmed using various analytical techniques, including UV-visible spectroscopy, FTIR spectroscopy, particle size analysis, scanning electron microscopy (SEM) and X-ray diffraction (XRD). In the UV-visible spectroscopy the synthesised nanoparticles was characterized with the maximum absorbance at 570 nm. SEM analysis showed the nanoparticles to be nearly cuboidal in shape with the size range of 108.0 nm to 252.2 nm at the 1,00,000x magnification. X-ray diffraction revealed particle sizes ranging from 4.19 nm to 26.95 nm with diffraction peaks at 38.05° and 31.67°, corresponding to lattice planes [6.56] and [100], indicating a polycrystalline wurtzite structure. The synthesized CuONPs exhibited significant antimicrobial activity against clinical pathogenic bacteria such as Escherichia coli, Bacillus cereus, Staphylococcus aureus and Proteus mirabilis, as well as fungicidal activity against phytopathogenic fungi including Alternaria solani, Rhizoctonia solani and Colletotrichum capsici. Additionally the photocatalytic activity of the Pseudomonas aeruginosa mediated CuONPs was estimated through the degradation of the triarylmethane dye-malachite Green.

Exploring phase transitions in CdSe: a machine learning and swarm intelligence approach

The phase transition of cadmium selenide (CdSe) from wurtzite to rocksalt structure has been the subject of extensive research. In this study, we present a novel approach combining machine learning potentials with swarm intelligence-based pathway sampling to elucidate the complex phase transition mechanisms in CdSe. We developed an accurate machine-learning (ML) potential for CdSe, validated against density functional theory calculations, achieving mean absolute errors (MAEs) of 1.8 meV/atom for energies and 33 meV/Å for forces. This potential was integrated with the pathway sampling via swarm intelligence and graph theory (PALLAS) method to explore the potential energy landscape and identify low-energy transition pathways. Our simulations revealed a complex network of transition pathways, and we discovered a multi-step transition mechanism involving an unexpected zinc blende intermediate phase, which appears to play a crucial role in facilitating the transition between wurtzite and rocksalt structures. This finding provides new insights into the structural flexibility of CdSe and offers an explanation for experimentally observed phenomena such as wurtzite/zinc blende coexistence in nanostructures. Our approach not only advances the fundamental understanding of phase transitions in CdSe but also establishes a powerful computational framework for exploring complex materials phenomena, opening new avenues for materials design and discovery in semiconductor systems.

Green-mediated sol-gel fabrication of CuO/ZnO nanoparticles from orange peel extract for environmental remediation: insights from x-ray diffraction analysis using various models

Abstract This study introduces an eco-friendly and simple approach for synthesizing zinc oxide (ZnO), copper oxide (CuO), and ZnO-CuO composite nanoparticles using orange peel extract, minimizing the use of harmful chemicals while enhancing their antibacterial and photocatalytic properties. The nanoparticles were annealed at 400 °C for 2 h in the air. Characterization was conducted using x-ray Diffraction (XRD), Dynamic Light Scattering, Fourier Transform Infrared Spectroscopy (FTIR), and UV-visible Spectroscopy. XRD revealed that ZnO and CuO nanoparticles crystallized in hexagonal wurtzite and monoclinic structures, respectively, with crystallite size and lattice strain analyzed through Williamson–Hall, Size-Strain Plot, Halder-Wagner, and Wagner-Aqua methods. FTIR spectra confirmed the presence of Zn-O and CuO bonds, verifying successful synthesis. The optical bandgaps measured were 3.07 eV for ZnO, 2.702 eV for CuO, and 1.842 eV for the ZnO-CuO nanocomposite. Antimicrobial efficacy, assessed via the disc diffusion method, showed the ZnO-CuO composite exhibited enhanced antibacterial activity against both gram-positive and gram-negative strains compared to individual ZnO and CuO. Photocatalytic experiments demonstrated that under sunlight, the ZnO-CuO nanocomposite achieved 78% degradation of 10 ppm methylene blue within 90 min, outperforming individual ZnO (55%) and CuO (38%). These results highlight the ZnO-CuO composite’s potential for effective dye degradation and environmental remediation applications.

Effect of Bias Voltage on the Microstructure and Photoelectric Properties of W-Doped ZnO Films.

W-doped ZnO (WZO) films were deposited on glass substrates by using RF magnetron sputtering at different substrate bias voltages, and the relationships between microstructure and optical and electrical properties were investigated. The results revealed that the deposition rate of WZO films first decreased from 8.8 to 7.1 nm/min, and then increased to 11.5 nm/min with the increase in bias voltage. After applying a bias voltage to the substrate, the bombardment effect of sputtered ions was enhanced, and the films transformed from a smooth surface into a compact and rough surface. All the films exhibited a hexagonal wurtzite structure with a strong (002) preferred orientation and grew along the c-axis direction. When the bias voltage increased, both the residual stress and lattice parameter of the films gradually increased, and the maximum grain size of 43.4 nm was achieved at -100 V. When the bias voltage was below -300 V, all the films exhibited a high average transmittance of ~90% in the visible light region. As the bias voltage increased, the sheet resistance and resistivity of the films initially decreased and then gradually increased. The highest FOM of 5.8 × 10-4 Ω-1 was achieved at -100 V, possessing the best comprehensive photoelectric properties.

Influence of annealing temperature of seed layer on the structural and optical properties of ZnO nanorods synthesized by SILAR and CBD techniques

ABSTRACT In this study, zinc oxide nanorods were synthesized using chemical bath deposition with a ZnO seed layer on glass substrates via successive ionic layer adsorption and reaction. The effect of annealing temperature on the seed layer was investigated using various characterization techniques. Results show that annealing temperature significantly influenced the morphology and quality of ZnO NRs. As the temperature increased from 0°C to 500°C, the nanorod length grew from 591 to 1008 nm. Optimal conditions were found at 450°C, with a growth rate of 4.2 nm/min and an aspect ratio of 11. The crystalline size ranged from 10.56 to 52.93 nm, confirmed by XRD analysis, showing the hexagonal wurtzite structure. The bandgap energy varied from 3.221 eV to 3.2656 eV, reflecting the impact of annealing on optical properties. Optical transmittance was highest at 0°C, decreasing from 57% to 13% as the annealing temperature increased.

Exploring the physicochemical properties and antifungal activity of zinc oxide nanoparticles

ABSTRACT In this study, zinc oxide nanoparticles were synthesized using the chemical precipitation method with zinc acetate dihydrate and sodium hydroxide as precursors. UV-Vis spectroscopy confirmed the formation of ZnONPs, showing a characteristic absorption peak at around 360–370 nm, corresponding to a band gap energy of approximately 3.2 eV. XRD analysis indicated the crystalline nature of ZnONPs with a hexagonal wurtzite structure. FTIR and EDS analyses confirmed the presence of ZnONPs in the component. TEM revealed nearly spherical ZnONPs with average particle sizes of 26.1 nm for bare ZnONPs and 24.6 nm for PVP-capped ZnONPs. BET measurements showed a higher specific surface area for PVP-capped ZnONPs. The antifungal efficacy of ZnONPs was tested against Phytophthora capsici at concentrations ranging from 20 to 100 ppm. Results demonstrated significant inhibition of fungal growth, especially with PVP-capped ZnONPs, with complete inhibition at concentrations ≥60 ppm after 12 to 48 hours of incubation.

Effect of Mn doping on microstructure and photocatalytic properties of ZnO nanoparticles synthesized via a hydrothermal method

Abstract Manganese-doped zinc oxide (Zn/Mn) nanostructures were synthesized via the hydrothermal method, varying the manganese content. The synthesized Zn/Mn nanostructures exhibit a hexagonal wurtzite structure with an average crystallite size ranging from 19 to 33 nm, as determined by X-ray diffraction (XRD) analysis. Increasing Mn concentration induces a blue shift in the energy bandgap (Eg) of the Zn/Mn nanostructures, decreasing it from 3.26 to 3.15 eV. The photocatalytic performance of these nanostructures was evaluated by studying the degradation of methylene blue (MB) under ultraviolet light irradiation. The incorporation of Mn content systematically enhanced the photocatalytic activity of ZnO, with the highest (73%) was observed in Zn/Mn_4 nanostructures. Additionally, the degradation mechanism has been addressed.