What is the effect of silver decorated ZnO nanoparticles on the SPR effect?5 answersSilver decorated ZnO nanoparticles have been found to have an effect on the surface plasmon resonance (SPR) effect. The incorporation of silver onto the ZnO surface leads to a red shift in the adsorption band towards the visible region, indicating the presence of localized surface plasmon resonance (LSPR) effect of the metallic silver on the surface of ZnO. The SPR effect caused by the silver modification of ZnO results in a decreased band gap of the ZnO/Ag composites compared to bare ZnO, enhancing light absorption and improving the separation of electron-hole pairs in the near-surface region of the semiconductor. The spatial separation of electron-hole pairs in silver decorated ZnO nanorods is considerably enhanced due to the LSPR effect derived from silver nanoparticles, leading to improved photocatalytic activity. Therefore, the presence of silver on ZnO nanoparticles enhances the SPR effect, resulting in improved optical and photocatalytic properties.
What are the long-term safety and efficacy outcomes of ZnO/Ag nanocomposites in clinical settings?5 answersZnO/Ag nanocomposites have shown promising antimicrobial activity against Staphylococcus aureus and Escherichia coli, eliminating more than 90% of inoculated bacteria. Additionally, Ag-ZnO/AgO nanocomposites have demonstrated inhibitory effects on the replication of Leishmania braziliensis, making them a potential treatment option for tegumentary leishmaniasis. ZnO-based nanomaterials, including ZnO nanorods, have exhibited significant antibacterial effects against both Gram-positive and Gram-negative bacteria, with smaller nanorods showing better activity. However, the long-term safety and efficacy outcomes of ZnO/Ag nanocomposites in clinical settings have not been specifically addressed in the provided abstracts. Further research is needed to evaluate the long-term effects and potential risks associated with the use of these nanocomposites in clinical applications.
How does the addition of graphene affect the increasing diameter of ZnO rod?5 answersThe addition of graphene to ZnO films leads to a decrease in the number of oxygen vacancies (VO), zinc vacancies (VZn), and oxygen interstitials (Oi). This decrease is attributed to the substitution of VO by Oi, resulting in the annihilation of equal numbers of acceptors and donors and no change in the net electron carrier density. Additionally, the incorporation of graphene into ZnO leads to a transition from VZn to the substitution of carbon for zinc (CZn). The formation of a CZn+2Oi complex is observed in graphene-doped ZnO thin films. However, the effect of graphene on the increasing diameter of ZnO rods is not mentioned in the provided abstracts.
What are the different methods to fabricate ZnO nanoflowers?5 answersZnO nanoflowers can be fabricated using different methods. One method is the sonochemical method, which is a simple, environmentally friendly, low-cost, and rapid method. Another method is the colloidal route, where an aqueous extract of Ganoderma lucidum is used as a reducing agent and stabilizer. A third method involves a three-step preparation method combining electrospinning, heat treatment, and hydrothermal synthesis. Additionally, ZnO nanoflowers can be synthesized using the seed layer-hydrothermal method, where a seed layer is deposited on a substrate and then subjected to hydrothermal growth. Finally, ZnO nanoflowers can be obtained by combining the spin-coating technique with the sol-gel method and hydrothermal growth.
How can the different methods to fabricate ZnO nanoflowers be improved?5 answersDifferent methods to fabricate ZnO nanoflowers can be improved in several ways. One approach is to use a sonochemical method, which is a simple, environmentally friendly, low-cost, and rapid method for synthesis. Another improvement is to fabricate Au-modified ZnO nanoflowers, which exhibit excellent gas sensing performance due to their regular and ordered three-dimensional flower-like structures. Additionally, the use of fungi extracts as reducing agents and stabilizers can enhance the synthesis of ZnO nanoflowers, resulting in particles with a large effective surface and high crystallinity. The morphological and photovoltaic properties of ZnO thin films can be controlled by adjusting the presence of NH3 and different additives, leading to improved energy conversion efficiencies in dye-sensitized solar cells. Finally, the ultimate morphology of ZnO flower-like nanostructures can be controlled by adjusting the amount of surfactant added to the precursor, which affects the thickness and shape of the petals.
How to analize Raman Spectra of ZnO nanorods?3 answersRaman spectra of ZnO nanorods can be analyzed using various techniques and approaches. One approach is the use of surface-enhanced Raman spectroscopy (SERS). SERS substrates based on ZnO/Au nanorods have been successfully fabricated, providing good sensitivity for Raman signal detection. Another approach is the application of the 3D phonon confinement model (PCM) for interpreting Raman spectra of ZnO nanoparticles. The PCM has been found to be applicable to both acoustic and optical modes, providing detailed information on the size-dependent shapes of the phonon bands. Additionally, the effect of nickel concentration on the formation of ZnO/NiO nanocomposites can be studied using Raman spectroscopy, with distinct Raman modes corresponding to the different phases of ZnO and NiO. Overall, these techniques and models offer valuable insights into the analysis of Raman spectra of ZnO nanorods.