Additional Defects Research Articles

Effect of MoO3 on Na2O–B2O3–CdO–ZnO glasses: Applications in optoelectronics, communication devices, and radiation shielding

The current study focuses on the physical and structural aspects of B2O3–CdO–ZnO–Na2O glasses that have been reinforced by MoO3 ions. The samples were experimentally prepared using a melt quenching procedure, and then the absence of strong peaks in the XRD spectra confirms their amorphous nature. A variety of optical, Raman, and radiationshielding qualities were evaluated and described. The structural changes in the material were investigated using FTIR and Raman spectra. The density of the samples rose when MoO3 was added, implying that BO3 was transformed into BO4 units. The transition of Mo6+ to Mo5+ ions is responsible for the reduction in band gap in these glasses. Because of the vacancy generated by the oxygen units, the Urbach energy increased, implying the generation of additional defects. The presence of diverse structures present in the structure of the glass was revealed by FTIR and Raman spectra, such as MoO6, BO3, BO4, metaborates, pyroborates, and so on. The transition of BO3 to BO4 units, which is crucial in density analyses, was also corroborated by Raman spectra. Using FLUKA simulation and XCOM estimations, the mass attenuation coefficient of the glasses improved with the amount of MoO3. At 15 keV, the half-value layer of 0.0103 cm, 0.01019 cm, 0.01016 cm, 0.0101 cm, and 0.01005 cm was obtained for glasses with an MoO3 concentration of 0, 0.5, 1, 1.5, and 2.0 mol% respectively. The optimum MoO3 concentration for fast and thermal neutron cross-sections was 0.5 and 2.0 mol% respectively. The glasses are viable materials for environmentally friendly and transparent radiation barriers in nuclear facilities.

Hypothalamic warm-sensitive neurons require TRPC4 channel for detecting internal warmth and regulating body temperature in mice

Precise monitoring of internal temperature is vital for thermal homeostasis in mammals. For decades, warm-sensitive neurons (WSNs) within the preoptic area (POA) were thought to sense internal warmth, using this information as feedback to regulate body temperature (Tcore). However, the cellular and molecular mechanisms by which WSNs measure temperature remain largely undefined. Via a pilot genetic screen, we found that silencing the TRPC4 channel in mice substantially attenuated hypothermia induced by light-mediated heating of the POA. Loss-of-function studies of TRPC4 confirmed its role in warm sensing in GABAergic WSNs, causing additional defects in basal temperature setting, warm defense, and fever responses. Furthermore, TRPC4 antagonists and agonists bidirectionally regulated Tcore. Thus, our data indicate that TRPC4 is essential for sensing internal warmth and that TRPC4-expressing GABAergic WSNs function as a novel cellular sensor for preventing Tcore from exceeding set-point temperatures. TRPC4 may represent a potential therapeutic target for managing Tcore.

Low carbon bainitic steel processed by ausforming: Heterogeneous microstructure and mechanical properties

Thermodynamic stability of austenite is a primary factor affecting mechanical properties of low-carbon bainitic steels. In this work, ausforming was applied to a low-carbon steel, in which additional dislocations and defects were induced in austenite prior to isothermal transformation of bainite at a relatively low temperature. Hence, the stability of the retained austenite was improved, and the formation of fresh martensite during the secondary stage of cooling was suppressed. Results of microstructure characterizations by electron backscatter diffraction (EBSD), X-ray diffraction (XRD), and dilatometry were examined. The correlations between the process parameters and developed heterogeneous microstructures were established. It was found that the volume fraction of retained austenite was greatly promoted along with the reductions of fresh martensite and bainitic ferrite. Tensile properties of the bainitic steel were enhanced due to the occurred heterogeneous microstructure and fair balance of its phase constituents. The significantly increased strengths were mainly attributed to microstructure refinement as well as the enrichment of geometrically necessary dislocations (GNDs) within the bainitic ferrite and retained austenite. Furthermore, a large fraction of retained austenite showed a significant impact on the enhancement of both uniform elongation and strength, benefitting from the transformation-induced plasticity (TRIP) effect. The presence of microcracks and tiny dimples with thick tearing edges in the vicinity of the inclusions in the fractographs were directly related to the refined microstructure, which certainly provided a remarkable ability to reduce the formation of macro/micro-cracks and prolong the post-necking. • Ausforming improves the thermodynamic stability of the retained austenite. • Ausformed microstructure with high GND densities hinder martensite transformation. • Strength and ductility are enhanced by the developed heterogeneous microstructure. • Microstructural refinement retards macro/microcracks formation up to fracture.

Assessment of the load-bearing capacity of materials and structures using a finite element model

The current technical condition of a multi-storey frame building structures is studied. The survey is carried out for individual structural elements of the object, which makes it possible to determine the actual technical condition of the building and its constituent elements. Additional damage and defects appeared at the object under study due to the forced break in construction. Verification calculations of the non-existent capacity of structures were performed based on the results of the technical condition monitoring. The existing real operational loads and impacts were taken into account in the calculations for the actual design schemes. The results of field studies were processed to develop a reconstruction project for a frame multi-storey building. Quantitative estimates of the actual quality indicators of load-bearing building structures were used. A computer-based verification calculation based on the application of a finite element model was performed for the construction of a cinema hall located in the frame building under study. Plots of internal forces in structures are obtained. It is concluded that the object under study is in a working technical condition.

Defect engineering and post-synthetic reduction of Cu based metal–organic frameworks towards efficient adsorption desulfurization

Adsorption desulfurization (ADS) is one of the most potential technologies for desulfurization of gasoline, while developing adsorbents with high sulfur capture capability to meet the strict environmental regulations remains a challenge. Here, a series of CuBDC-x adsorbents containing additional defects and enhanced adsorption sites via modulator-induced defect engineering and subsequent post-synthetic reduction strategy were synthesized. The optimal CuBDC-1 samples showed a remarkable sulfur adsorption capacity of 41.1 mg S/g in model fuel, which is 104.5 % higher than that of original CuBDC. The Cu+ rather than Cu2+ cations in MOFs were found to be the main adsorption sites for mercaptan molecules. This work offers a new insight into developing high-efficiency adsorbent for ultra-deep desulfurization.

The role of surface states and point defects on optical properties of InGaN/GaN multi-quantum wells in nanowires grown by molecular beam epitaxy

The optical properties of nanowire-based InGaN/GaN multiple quantum wells (MQWs) heterostructures grown by plasma-assisted molecular beam epitaxy are investigated. The beneficial effect of an InGaN underlayer grown below the active region is demonstrated and assigned to the trapping of point defects transferred from the pseudo-template to the active region. The influence of surface recombination is also investigated. For low InN molar fraction value, we demonstrate that AlO x deposition efficiently passivate the surface. By contrast, for large InN molar fraction, the increase of volume non-radiative recombination, which we assign to the formation of additional point defects during the growth of the heterostructure dominates surface recombination. The inhomogeneous luminescence of single nanowires at the nanoscale, namely a luminescent ring surrounding a less luminescent centre part points towards an inhomogeneous spatial distribution of the non-radiative recombination center tentatively identified as intrinsic point defects created during the MQWs growth. These results can contribute to improve the performances of microLEDs in the visible range.

Micro defects formation and dynamic response analysis of steel plate of quasi-cracking area subjected to explosive load

As the protective component, steel plate had attracted extensive attention because of frequently threats of explosive loads. In this paper, the evolution of microstructure and the mechanism of damage in the quasi-cracking area of steel plate subjected to explosive load were discussed and the relationships between micro defects and dynamic mechanical response were revealed. After the explosion experiment, five observation points were selected equidistant from the quasi-cracking area of the section of the steel plate along the thickness direction, and the characteristics of micro defects at the observation points were analyzed by optical microscope (OM), scanning electron microscope (SEM) and electron back-scattered diffraction (EBSD). The observation result shows that many slip bands (SBs) appeared, and the grain orientation changed obviously in the steel plate, the two were the main damage types of micro defects. In addition, cracks, peeling pits, grooves and other lager micro defects were appeared in the lower area of the plate. The stress parameters of the observation points were obtained through an effective numerical model. The mechanism of damage generation and crack propagation in the quasi-cracking area were clarified by comparing the specific impulse of each observation point with the corresponding micro defects. The result shows that the generation and expansion of micro defects are related to the stress area (i.e. the upper compression area, the neutral plane area, and the lower tension area). The micro defects gather and expand at the grain boundary, and will become macroscopic damage under the continuous action of tensile stress. Besides, the micro defects at the midpoint of the section of the steel plate in the direction away from the explosion center (i.e. the horizontal direction) were also studied. It was found that the specific impulse at these positions were much smaller than that in the thickness direction, the micro defects were only SBs and a few micro cracks, and the those decreased with the increase of the distance from the explosion center.

Recrystallization effects in spray-pyrolyzed Nb2O5 thin films induced by 100 MeV O7+ swift heavy ion beam irradiation

In this work, the influence of 100 MeV O7+ high energy swift heavy ion beam irradiation at varied fluences on the modification of properties of spray-deposited thin niobium pentoxide (Nb2O5) film is reported. The XRD patterns indicate tetragonal structure for pristine polycrystalline Nb2O5 film and partial amorphous nature for the irradiated samples in corroboration with the Raman spectra of the respective samples. The crystallite size is observed to reduce overall compared to that of the pristine film, however, a peaking is observed for 5x1012 ions/cm2 fluence within the irradiated films which is due to the high energy irradiation-induced defect formation and recrystallization effects. It is important to note that the defect density increases with fluence and recrystallisation occurs at 5x1012 ions/cm2, with further amorphization induced at much higher fluences. The generation of additional defect levels lowers the optical band gap. The direct and indirect band gaps were found to reduce upon irradiation compared to that of the pristine Nb2O5 film. The atomic force microscopic analysis reveals decrease in surface roughness of the irradiated samples from 5.9 nm to 10.1 nm compared to the pristine sample. Oxygen ion beam changes their morphology into network-like structures in a controllable manner which mainly depends on electronic energy loss occurring within the Nb2O5 lattice. Variations in transport parameters measured using Hall effect reveal that lower fluence yields less damage accumulation and does not cause significant change in properties of the sample. As fluence increases, vivid modifications originate from the production of significant density of point defects. At the critical fluence, recrystallisation is observed. These results are discussed in detail using the calculated parameters like crystallite size, Urbach energy, defect density and by correlating them with the observed optical and electrical data obtained from different techniques.

Resistance degradation in sputtered sodium potassium niobate thin films and its relationship to point defects

The reliability of piezoelectric thin films is crucial for piezoelectric micro-electromechanical system applications. The understanding of resistance degradation in piezoelectric thin films requires knowledge about point defects. Here, we show the resistance degradation mechanism in the lead-free alternative sodium potassium niobate (KNN) thin films and the relationship to point defects in both field-up and field-down polarities. The conduction mechanism of KNN thin films is found to be Schottky-limited. Furthermore, a reduction in Schottky barrier height accompanies the resistance degradation resulting from interfacial accumulation of additional charged defects. We use thermally stimulated depolarization current measurements and charge-based deep level transient spectroscopy to characterize the defects in KNN thin films. Our results show that oxygen vacancies accumulate at the interface in field-up polarity, and multiple defects accumulate in field-down polarity, potentially oxygen vacancies and holes trapped by potassium vacancies. We use wafer deposition variation to create samples with different film properties. Measurement results from these samples correlate resistance degradation with the defect concentration. We find the natural logarithm of leakage current to be linearly proportional to the defect concentration to the power of 0.25. The demonstrated analysis provides a precise and meaningful process assessment for optimizing KNN thin films.

Origin of trap assisted tunnelling in ammonia annealed SiC trench MOSFETs

The interface between silicon carbide (SiC) and silicon dioxide (SiO2) is of considerable importance for the performance and reliability of 4H-SiC (trench) metal oxide semiconductor field effect transistors (MOSFETs) and various different post oxidation anneals (POAs) have been used to optimize its quality. Whereas nitric oxide (NO) POA leads to very reliable and well performing MOSFETs, ammonia (NH3) can further improve the device performance, however, at the cost of the gate oxide (GOX) reliability, e.g. leading to trap assisted tunneling (TAT). We investigate the origin of TAT and GOX leakage in differently annealed gate oxides experimentally, using 4H-SiC trench MOSFETs, and theoretically, using Density Functional Theory (DFT) simulations. Our findings reinforce the view that the NO anneal for SiC devices results in the best overall quality as devices annealed in NH3 and nitrogen N2 show higher oxide charge density and leakage currents. DFT simulations demonstrate that, contrary to what has often been assumed so far, NH3 annealing leads to the formation of additional hydrogen related defects, which open leakage paths in the oxide otherwise not present in NO treated oxides.

GATA1 controls numbers of hematopoietic progenitors and their response to autoimmune neuroinflammation

AbstractGATA-binding factor 1 (GATA1) is a transcription factor that governs the development and function of multiple hematopoietic cell lineages. GATA1 is expressed in hematopoietic stem and progenitor cells (HSPCs) and is essential for erythroid lineage commitment; however, whether it plays a role in hematopoietic stem cell (HSC) biology and the development of myeloid cells, and what that role might be, remains unclear. We initially set out to test the role of eosinophils in experimental autoimmune encephalomyelitis (EAE), a model of central nervous system autoimmunity, using mice lacking a double GATA-site (ΔdblGATA), which lacks eosinophils due to the deletion of the dblGATA enhancer to Gata1, which alters its expression. ΔdblGATA mice were resistant to EAE, but not because of a lack of eosinophils, suggesting that these mice have an additional defect. ΔdblGATA mice with EAE had fewer inflammatory myeloid cells than the control mice, suggesting that resistance to EAE is caused by a defect in myeloid cells. Naïve ΔdblGATA mice also showed reduced frequency of CD11b+ myeloid cells in the blood, indicating a defect in myeloid cell production. Examination of HSPCs revealed fewer HSCs and myeloid cell progenitors in the ΔdblGATA bone marrow (BM), and competitive BM chimera experiments showed a reduced capacity of the ΔdblGATA BM to reconstitute immune cells, suggesting that reduced numbers of ΔdblGATA HSPCs cause a functional deficit during inflammation. Taken together, our data show that GATA1 regulates the number of HSPCs and that reduced GATA1 expression due to dblGATA deletion results in a diminished immune response following the inflammatory challenge.

Конечно-элементное моделирование состояния металлических конструкций каркасного здания

For the considered groups of structures - metal trusses, beams, columns, landings and marches of a multi-storey frame building, a continuous visual and detailed instrumental examination was performed. For load-bearing structures, verification calculations of their bearing capacity were performed. Based on a comparison of the defects identified during the inspection and the results of verification calculations, an assessment of the technical condition was made for individual structures, for each group of structural elements, as well as for the building as a whole. For structures with defects and damage, recommendations are given for their restoration and repair. Additional damages and defects were recorded, the appearance of which is associated at the object under study due to a forced break in the production of construction work. The results of surveys and calculations showed that the technical condition of landings and marches can be considered generally efficient. The results of the verification calculation showed that the technical condition of the metal columns as a whole can be considered efficient. The results of the verification calculation on the computer of metal truss structures are presented in the form of a mosaic and diagrams of internal forces. When performing verification calculations, the finite element method was applied.

Impact of Tb doping on luminescence properties of LiCaAlF6 phosphor prepared in argon atmosphere and charge transfer mechanism

This work focuses on the synthesis and characterization of Tb doped LiCaAlF6 phosphor for its OSL dosimetry properties. The phosphor has been prepared by melting method. XRD shows the formation of LiCaAlF6 with enrichment of CaF2. The excess availability of Ca2+ions are advantageous in incorporation of Tb dopant. The photoluminescence studies show the increase in the luminescence intensity after Tb doping by showing strong emission corresponding to 5D4 → 7FJ (J = 6, 5, 4, 3) transitions with a prominent green emission transition 5D4 → 7F5 at 540 nm. Further, Tb ion exist in Tb3+ and Tb4+ state as observed from XPS. The incorporation of Tb4+ ion is difficult to achieve and its presence in the host might also increase the of number of trapping states. The OSL studies of LiCaAlF6: Tb show high intensity under blue light stimulation for beta irradiation in the dose range 0.05–10Gy. The OSL sensitivity of LiCaAlF6: Tb phosphor is found to be ∼8 times higher to that of commercially available Al2O3: C. The phosphor has shown dose linearity in the range of 0.05–10Gy and minimum detectable dose (MDD)∼6.95 μGy. The enhanced sensitivity may be attributed to the additional defect centers due to excess CaF2 with mixed oxidation state of Tb3+ and Tb4+ ions. The enhancement of OSL signal of LiCaAlF6: Tb in comparison to Al2O3:C has been discussed based on charge compensation mechanism. These results indicate that LiCaAlF6: Tb phosphor prepared via melting method in Ar gas atmosphere shows good OSL properties and has potential application in radiation dosimetry.

Nitrogen-Doped Hollow Carbon Spheres Based on Schiff Base Reaction as an Anode Material for High-Performance Lithium and Sodium Ion Batteries.

Nitrogen-doped carbon has great potential in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs), considering N-doping can not only improve the surface wettability of carbon materials, but also accelerate charge transfer by generating additional defects. However, designing carbon materials with a high nitrogen content and uniform distribution using conventional doping methods remains a challenge. In this study, a hollow carbon sphere with an ultrahigh nitrogen content of 9.58 wt % was successfully fabricated by rationally designing Schiff base chemistry (PTA-NHCS-700). Stable hierarchical pore structures, moderate defects, and large specific surface areas were formed during the carbonization process. Excellent electrochemical performance was observed in LIBs (204.2 mAh g-1 after 7000 cycles at 5 A g-1 ) and SIBs (154.2 mAh g-1 after 10000 cycles at 5 A g-1 ). This study not only promotes the development of efficient carbon anode materials for LIBs and SIBs, but also provides a novel idea for the doping of heteroatoms with special chemical structures.

Recoil energy dependence of primary radiation damage in tungsten from cascade overlap with voids

Models of radiation damage accumulation often assume a constant rate of additional primary damage formation during prolonged irradiation. However, molecular dynamics simulations have shown that the presence of pre-existing radiation-induced defects modifies the numbers of additional defects formed from individual cascades. In this work, we study the formation of defects in tungsten for a range of primary recoil energies, for cascades that fully overlap with pre-existing voids of different sizes. We extend a recent model describing defect production in the presence of pre-existing damage to also account for the recoil energy dependence, and parametrize the extension based on our simulation data. We also analyze the morphology of the primary damage from cascades overlapping with voids, and show that the in-cascade formation of 〈100〉 dislocation loops in such events is more dependent on the size of the pre-existing void, than on the energy of the primary recoil.

Surface Passivation of Layered MoSe2 via van der Waals Stacking of Amorphous Hydrocarbon.

Development of efficient surface passivation methods for semiconductor devices is crucial to counter the degradation in their electrical performance owing to scattering or trapping of carriers in the channels induced by molecular adsorption from the ambient environment. However, conventional dielectric deposition involves the formation of additional interfacial defects associated with broken covalent bonds, resulting in accidental electrostatic doping or enhanced hysteretic behavior. In this study, centimeter-scaled van der Waals passivation of transition metal dichalcogenides (TMDCs) is demonstrated by stacking hydrocarbon (HC) dielectrics onto MoSe2 field-effect transistors (FETs), thereby enhancing the electric performance and stability of the device, accompanied with the suppression of chemical disorder at the HC/TMDCs interface. The stacking of HC onto MoSe2 FETs enhances the carrier mobility of MoSe2 FET by over 50% at the n-branch, and a significant decrease in hysteresis, owing to the screening of molecular adsorption. The electron mobility and hysteresis of the HC/MoSe2 FETs are verified to be nearly intact compared to those of the fabricated HC/MoSe2 FETs after exposure to ambient environment for 3months. Consequently, the proposed design can act as a model for developing advanced nanoelectronics applications based on layered materials for mass production.

Role of MMP3 and fibroblast-MMP14 in skin homeostasis and repair

Early lethality of mice with complete deletion of the matrix metalloproteinase MMP14 emphasized the proteases’ pleiotropic functions. MMP14 deletion in adult dermal fibroblasts (MMP14Sf-/-) caused collagen type I accumulation and upregulation of MMP3 expression. To identify the compensatory role of MMP3, mice were generated with MMP3 deletion in addition to MMP14 loss in fibroblasts. These double deficient mice displayed a fibrotic phenotype in skin and tendons as detected in MMP14Sf-/- mice, but no additional obvious defects were detected. However, challenging the mice with full thickness excision wounds resulted in delayed closure of early wounds in the double deficient mice compared to wildtype and MMP14 single knockout controls. Over time wounds closed and epidermal integrity was restored. Interestingly, on day seven, post-wounding myofibroblast density was lower in the wounds of all knockout than in controls, they were higher on day 14. The delayed resolution of myofibroblasts from the granulation tissue is paralleled by reduced apoptosis of these cells, although proliferation of myofibroblasts is induced in the double deficient mice. Further analysis showed comparable TGFβ1 and TGFβR1 expression among all genotypes. In addition, in vitro, fibroblasts lacking MMP3 and MMP14 retained their ability to differentiate into myofibroblasts in response to TGFβ1 treatment and mechanical stress. However, in vivo, p-Smad2 was reduced in myofibroblasts at day 5 post-wounding, in double, but most significant in single knockout, indicating their involvement in TGFβ1 activation. Thus, although MMP3 does not compensate for the lack of fibroblast-MMP14 in tissue homeostasis, simultaneous deletion of both proteases in fibroblasts delays wound closure during skin repair. Notably, single and double deficiency of these proteases modulates myofibroblast formation and resolution in wounds.

Characterization and antibacterial activity of Ti doped ZnO nanorods prepared by hydrazine assisted wet chemical route

In this study, a simple hydrazine assisted wet chemical method was used to prepare pure and Ti doped ZnO nanorods . The structural properties of pure and Ti doped ZnO nanorods were investigated by XRD analysis. Williamson-Hall (W–H) method was used to determine the crystallite size , strain and dislocation density of the samples. TEM analysis revealed rod like morphology for Ti doped ZnO nanoparticles . The presence of elements such as Zn, Ti and O of the doped sample was confirmed by EDS. XPS spectrum suggests that Ti 4+ ions well substitute Zn 2+ ions in doped nanocrystal . The Raman study further established the formation of ZnO wurtzite structure in both pure and Ti doped ZnO nanorods. The band gap of pure and Ti doped ZnO nanorods were estimated by the Tauc relation as 3.03 eV and 2.91 eV respectively. From the PL spectra, it is observed that the intensity of the polychromatic defect emissions of Ti doped ZnO nanorods is higher than pure ZnO, with some additional defect emissions. The antibacterial activity of Ti doped ZnO nanorods slightly decreased against gram-positive and gram-negative bacteria when compared to pure ZnO. • Synthesis of pure and Ti doped ZnO nanorods by a facile hydrazine assisted wet chemical method. • Confirmation of substitution of Ti 4+ ions into Zn 2+ ions in doped nanocrystal from XPS spectrum. • The band gap of pure and Ti doped ZnO nanorods were estimated by the Tauc relation as 3.03 eV and 2.91 eV. • Intensity of the polychromatic defect emissions of Ti doped ZnO nanorods is higher than pure ZnO. • The antibacterial activity of Ti doped ZnO nanorods is slightly lower than pure ZnO and higher than certain doped ZnO nanostructures.

Abnormal enhancement to the quality factors of carbon nanotube via defects engineering

Low quality (Q) factor is often the limiting factor for high performance carbon nanotube (CNT) resonators. The most commonly used approach to enhance the Q factor of CNTs is to reduce/eliminate the intrinsic defects. Herein, we show surprisingly that hole defects of suitable size and position are able to enhance the Q factor of CNT, which strongly contradicts to the common notion that the presence of defects promote intrinsic dissipation via defects dissipation. By analyzing the strain distribution, we find that such abnormal enhancement in Q factor of defected CNT originates from a coupling competition mechanism between the atomic mismatch around defected atoms and the thermoelastic damping. Although the presence of holes will introduce an additional defect dissipation source, suitable holes are capable of reducing the energy dissipation arisen from the thermoelastic damping, through changing the spatial strain field of defected CNT. This coupling competition mechanism provides a new route for designing high performance CNT resonators via defects engineering.

Physical property modifications with transition metal doping in nanostructured Zn1-xNixO (x = 0.03, 0.05); synthesized by chemical co-precipitation technique

Present work demonstrate the structural and optical property study of Zn1-xNixO (x= 0.03, 0.05) nanoparticles (NPs). These samples have been prepared by simple chemical co-precipitation method. Finally these samples are annealed at 500°C for 3 hours. Structural characterization has been performed by doing X-Ray diffraction (XRD) at room temperature. The XRD patterns confirm the hexagonal wurzite structure for these samples. We have estimated the lattice parameters (a & c) and determine the c/a ratio of respective samples after structural analysis. Morphology of these nanoparticles has been investigated by performing SEM. In addition UV-visible and Photoluminescence (PL) study has been performed. PL emission spectra show a broad UV emission peak. Doping at the Zn-site by Ni ions could induce inter-band levels within the band gap. Transition between those levels may responsible for broadening of the UV peak. In addition defect mediated visible emission has also been observed in the PL study. Further to investigate the effect of doping on microstructure, Raman spectra of Zn1-xNixO samples are taken. Wurzite ZnO belongs to space group: C4 6v and consequently six first order phonon modes are expected to appear in the Raman spectra. Raman scattering has been analysed according to the existing literature and details of analysis are presented in this work.