Synergetic effect of Sn doped ZnO nanoparticles synthesized via ultrasonication technique and its photocatalytic and antibacterial activity

A density functional theory study on the potential application of Ni and Co doped ZnO nanosheets as a carrier for ciclopirox anticancer drug

The Ni and Co doping effect on the ciclopirox (CPX) drug delivery performance of a ZnO ‎nanosheet (ZnO-NS) was investigated theoretically. Doping Ni and Co metals into the ZnO-NS ‎increased the adsorption energy of CPX from -7.9 to -27.4 and -31.7 kcal/mol, respectively. ‎The CPX adsorption reduced the ZnO-NS gap (Eg) from 3.81 to 3.46 eV, while the CPX ‎adsorption reduced the Eg of the Ni- and Co-doped ZnO-NS from 2.74 and 2.68 eV to 1.87 and ‎‎1.71 eV, respectively. The CPX adsorption performance increased after doping process. A drug ‎release mechanism was introduced in cancerous tissues based on the PH.‎.

Sn Bulk Phase Doping and Surface Modification on Ti4 O7 for Oxygen Reduction to Hydrogen Peroxide

Developing stable and highly selective two-electron oxygen reduction reaction (2e- ORR) electrocatalysts for producing hydrogen peroxide (H2 O2 ) is considered a major challenge to replace the anthraquinone process and achieve a sustainable green economy. Here, we doped Sn into Ti4 O7 (D-Sn-Ti4 O7 ) by simple polymerization post-calcination method as a high-efficiency 2e- ORR electrocatalyst. In addition, we also applied plain calcination after the grinding method to load Sn on Ti4 O7 (L-Sn-Ti4 O7 ) as a comparison. However, the performance of L-Sn-Ti4 O7 is far inferior to that of the D-Sn-Ti4 O7 . D-Sn-Ti4 O7 exhibits a starting potential of 0.769 V (versus the reversible hydrogen electrode, RHE) and a high H2 O2 selectivity of 95.7 %. Excitingly, the catalyst can maintain a stable current density of 2.43 mA ⋅ cm-2 for 3600 s in our self-made H-type cell, and the cumulative H2 O2 production reaches 359.2 mg ⋅ L-1 within 50,000 s at 0.3 V. The performance of D-Sn-Ti4 O7 is better than that of the non-noble metal 2e- ORR catalysts reported so far. The doping of Sn not only improves the conductivity but also leads to the lattice distortion of Ti4 O7 , further forming more oxygen vacancies and Ti3+ , which greatly improves its 2e- ORR performance compared with the original Ti4 O7 . In contrast, since the Sn on the surface of L-Sn-Ti4 O7 displays a synergistic effect with Tin+ (3≤n≤4) of Ti4 O7 , the active center Tin+ dissociates the O=O bond, making it more inclined to 4e- ORR.

Effect of tin concentrations on the elemental and optical properties of zinc oxide thin films

Pure zinc oxide and Sn-doped ZnO thin films were deposited on a pre-heated glass substrate from tin (II) chloride dihydrate (SnCl2.2H2O) and zinc acetate (Zn(CH3COO))2 precursors using spray pyrolysis technique. The doped films were achieved by adding various quantities of (SnCl2. 2H2O) precursor to the solution of zinc acetate in volume percent range of 0-10. Rutherford Backscattering Spectrometry (RBS) was used to characterise the prepared films to determine their thickness and elemental composition. To examine the films' optical characteristics, a UV spectrometer operating at room temperature and covering a wavelength range of 300-1100 nm was employed. The film's thickness and composition show that as the volume of Sn in the thin films increases, so does the film's thickness. With average transmittance values up to 70 %, all the films are quite transparent in the visible region of the electromagnetic spectrum and have a significant UV cut-off at roughly 380 nm. The reflectivity of Sn-doped ZnO films is seen to be independent of the volume of Sn in the films, and the reflectivity of the films diminishes as the wavelength increases. Sn-doped ZnO thin film has an optical band gap of 3.14-3.18 eV. The properties of the thin film produced make it suitable for solar energy collection and improve the efficiency of solar energy system, various optoelectronics devices and sensor.

Effect of doping and loading Parameters on photocatalytic degradation of brilliant green using Sn doped ZnO loaded CSAC

Sn doped ZnO loaded cotton stalk activated carbon (Sn-ZnO/CSAC) was prepared by chemical precipitation method, and the products were characterized. The XRD resultants confirm that the presence of hexagonal wurtzite phase of the bare ZnO. Furthermore, particular particle size gradually decreases (21.49 nm) due to doping and loading. UV-Vis absorption intensity of doped/loaded sample was red-shifted and then PL intensity is reduced. The photocatalytic performances of bare, Sn-doped ZnO and Sn-ZnO/CSAC was estimated by photodegradation of brilliant green (BG) under sunlight. The photodegradation of BG dye in 120 min over Sn-doped ZnO/CSAC is nearly 96.52%, which is considerably improved than bare ZnO (72.60%), respectively.

Fabrication of ZnO@Plant Polyphenols/Cellulose as Active Food Packaging and Its Enhanced Antibacterial Activity

To investigate the efficient use of bioresources and bioproducts, plant polyphenol (PPL) was extracted from larch bark and further applied to prepare ZnO@PPL/Cel with cellulose to examine its potential as an active package material. The structure and morphology were fully characterized by XRD, SEM, FTIR, XPS and Raman spectra. It was found that PPL is able to cover ZnO and form a coating layer. In addition, PPL cross-links with cellulose and makes ZnO distribute evenly on the cellulose fibers. Coating with PPL creates a pinecone-like morphology in ZnO, which is constructed by subunits of 50 nm ZnO slices. The interactions among ZnO, PPL and cellulose have been attributed to hydrogen bonding, which plays an important role in guiding the formation of composites. The antibacterial properties against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) were tested by the inhibition zone method. Our composite ZnO@PPL/Cel has superior antibacterial activity compared to ZnO/Cel. The antibacterial mechanism has also been elaborated on. The low cost, simple preparation method and good performance of ZnO@PPL/Cel suggest the potential for it to be applied as active food packaging.

In situ synthesis of advantageously united copper stannate nanoparticles for a new high powered supercapacitor electrode

A novel CuNi2O4@SnS@rGO/NF multicomponent hybrid material leads to fast ion/electron transfers at the electrode/electrolyte interface.

pH Shock-promoted lysozyme corona for efficient pathogenic infections treatment: Effects of surface chemistry of mesoporous silica nanoparticles and loading method

The emergence of antibiotic resistant bacteria because of the antibiotics abusement was the motivation to develop the effective alternatives to traditional antibiotics. Hence, various lysozyme corona were prepared through the physical and covalent attachment of lysozyme molecules onto either the bare or carboxyl-functionalized mesoporous silica particles. The prepared samples were characterized by STEM, TGA/DTA, zeta potential, FTIR, UV-vis and CD spectroscopic methods. All the prepared lysozyme-coated particles exhibited an efficient antibacterial activity against Listeria monocytogenes, as a case study, in vitro with no cytotoxicity. The minimal inhibition concentration (MIC) of the lysozyme-physically adsorbed bare and carboxyl-functionalized mesoporous silica nanoparticles (L-MS and L-ads-CMS, respectively) and the lysozyme-covalently attached carboxyl-functionalized MS particles (L-cov-CMS) was 2, 5.3 and 1.7 folds lower than that of the free lysozyme, respectively. Additionally, for the first time, it was reported that the pretreatment of lysozyme corona of L-ads-CMS through inducing a pH-shock can lead to the enhancement of antibacterial properties thereof. This behavior was associated to the controlled release of the immobilized lysozyme molecules and their conformational stability. These natural antibacterial lysozyme-coated silica nanoparticles showing the "pH-shock enhanced activity" could be of utmost interest for design of the highly active enzyme-modified nanoparticles.

Comparison of characteristics and biocompatibility of green synthesized iron oxide nanoparticles with chemical synthesized nanoparticles

Iron oxide nanoparticles synthesis is an expanding area of research due of their magnetic properties and possible applications in several novel technologies. FeONPs are indispensable in the biomedical field for diagnosis, treatments and drug delivery and in bioremediation applications. The synthesis route of nanoparticles is a major concern because biological methods are eco-friendly, and chemical methods are considered toxic. The objective of this study is to synthesize FeONPs by two different methods and to compare their properties and efficiency in applications. FeONPs were synthesized and characterized by microscopic and various spectroscopic techniques. The synthesized FeONPs were screened for their cytotoxic activity on PBMCs using MTT assay and found to exhibit good biocompatibility. Moreover, the GS FeONPs exhibited potential antibacterial activities and meanwhile showed less toxicity in brine shrimp lethality assay. Hence, these nanoparticles are biocompatible, environmentally safe and can be utilized in many medical applications.