Uncovering Atomic‐Scale Stability and Reactivity in Engineered Zinc Oxide Electrocatalysts for Controllable Syngas Production

In this study, scalable, flame spray synthesis is utilized to develop defective ZnO nanomaterials for the concurrent generation of H₂ and CO during electrochemical CO₂ reduction reactions (CO₂RR). The designed ZnO achieves an H₂/CO ratio of ≈1 with a large current density (j) of 40 mA cm^?2 during long‐term continuous reaction at a cell voltage of 2.6 V. Through in situ atomic pair distribution function analysis, the remarkable stability of these ZnO structures is explored, addressing the knowledge gap in understanding the dynamics of oxide catalysts during CO₂RR. Through optimization of synthesis conditions, ZnO facets are modulated which are shown to affect reaction selectivity, in agreement with theoretical calculations. These findings and insights on synthetic manipulation of active sites in defective metal‐oxides can be used as guidelines to develop active catalysts for syngas production for renewable power‐to‐X to generate a range of fuels and chemicals.     

In vitro and molecular docking analysis of chalconeimine derivatives with α-glucosidase

It is known that α-glucosidase is linked with the antioxidant activity. Therefore, it is of interest to document the in- vitro and molecular docking analysis of chalconeimine derivatives with α-glucosidase (PDB ID: 2ZEO) for further consideration.     

Characterization of zinc oxide nanocrystals with different morphology for application in ultraviolet‐light photocatalytic performances on rhodamine B

ZnO nanostructures of different morphology (nanorods, nano‐leaf, nanotubes) were favourably grown using a chemical precipitation process. The prepared ZnO nanostructures were characterized systematically using absorption spectroscopy, emission spectroscopy, X‐ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared studies. XRD results showed the hexagonal wurtzite phase of the synthesized ZnO nanostructures. Structural properties such as average crystallite size, lattice constants, volume of the unit cell, atomic fraction, and structural bonds were also studied. The optical band gap of the synthesized ZnO nanocrystals varied from 3.52 eV to 3.69 eV with high quantum yield of the blue emission (~420 nm). Urbach energy for ZnO nanocrystals was calculated to be 0.702 eV, 0.901 eV, and 0.993 eV for nanorods, nano‐leaf, and tube like ZnO crystals, respectively. Morphology of the fabricated nanostructures was investigated using SEM. Photocatalytic degradation of rhodamine B (Rh B) in solution under UV irradiation was explored with different ZnO morphology. Photocatalytic experiments showed that ZnO nano‐leaf had a higher degradation rate of photocatalytic activity of photodegrading Rh B compared with the other tube shape and rods shape nanostructures. The Rh B dye degraded considerably by ～79.05%, 74.41%, and 69.8% within 120 min in the presence of the as‐fabricated fern nano‐leaf, nanotubes, and nanorods of the ZnO nanocrystals at room temperature.     

Green synthesis of ZnO nanoparticles for antimicrobial and vegetative growth applications: A novel approach for advancing efficient high quality health care to human wellbeing

The present work aims to synthesize zinc oxide (ZnO) nanoparticles via green approaches using leaf extract of Parthenium hysterophorus. UV–vis and FT-IR tests confirmed the existence of biomolecules, active materials, and metal oxides. The X-ray diffraction structural study exposes the ZnO nanoparticles formation with hexagonal phase structures. SEM and TEM analysis reveal surface morphologies of ZnO nanoparticles and most of them are spherical with a size range of 10 nm. ZnO nanoparticles were revealed strong antimicrobial activity against both bacterial and fungal strains. The germination of seeds and vegetative growth of Sesamum indicum has been greatly improved.     

Highly luminescent CdTe/CdS/ZnO core/shell/shell quantum dots fabricated using an aqueous strategy

To create core/shell/shell quantum dots (QDs) with high stability against a harmful chemical environment, CdTe/CdS QDs were coated with a ZnO shell in an aqueous solution. An interfaced CdS layer sandwiched between a CdTe core and ZnO shell provided relaxation of the strain at the core/shell interface since lattice parameters of CdS are intermediate between those of CdTe and ZnO. The photoluminescence (PL) peak wavelength of the core/shell/shell QDs was shifted from 569 to 615 nm by adjusting the size of CdTe cores and thickness of CdS and ZnO shells, along with the highest PL quantum yield of the core/shell/shell QDs reaching 80%, which implies promising applications in the field of biomedical labeling. Due to the decrease of surface defects, it was observed that PL lifetimes significantly increased at room temperature as follows: 29.6 34.2, and 47.5 ns for CdTe (537 nm), CdTe/CdS (555 nm) and CdTe/CdS/ZnO (581 nm) QDs, respectively. Copyright © 2012 John Wiley & Sons, Ltd.     

Fabrication of Nano-engineered Transparent Conducting Oxides by Pulsed Laser Deposition

Nanosecond Pulsed Laser Deposition (PLD) in the presence of a background gas allows the deposition of metal oxides with tunable morphology, structure, density and stoichiometry by a proper control of the plasma plume expansion dynamics. Such versatility can be exploited to produce nanostructured films from compact and dense to nanoporous characterized by a hierarchical assembly of nano-sized clusters. In particular we describe the detailed methodology to fabricate two types of Al-doped ZnO (AZO) films as transparent electrodes in photovoltaic devices: 1) at low O₂ pressure, compact films with electrical conductivity and optical transparency close to the state of the art transparent conducting oxides (TCO) can be deposited at room temperature, to be compatible with thermally sensitive materials such as polymers used in organic photovoltaics (OPVs); 2) highly light scattering hierarchical structures resembling a forest of nano-trees are produced at higher pressures. Such structures show high Haze factor (>80%) and may be exploited to enhance the light trapping capability. The method here described for AZO films can be applied to other metal oxides relevant for technological applications such as TiO₂, Al₂O₃, WO₃ and Ag₄O₄.     

Square‐Centimeter‐Sized High‐Efficiency Polymer Solar Cells: How the Processing Atmosphere and Film Quality Influence Performance at Large Scale

Organic solar cells based on two benzodithiophene‐based polymers (PTB7 and PTB7‐Th) processed at square centimeter‐size under inert atmosphere and ambient air, respectively, are investigated. It is demonstrated that the performance of solar cells processed under inert atmosphere is not limited by the upscaling of photoactive layer and the interfacial layers. Thorough morphological and electrical characterizations of optimized layers and corresponding devices reveal that performance losses due to area enlargement are only caused by the sheet resistance of the transparent electrode reducing the efficiency from 9.3% of 7.8% for PTB7‐Th in the condition that both photoactive layer and the interfacial layers are of high layer quality. Air processing of photoactive layer and the interfacial layers into centimeter‐sized solar cells lead to additional, but only slight, losses (<10%) in all photovoltaic parameters, which can be addressed to changes in the electronic properties of both active layer and ZnO layers rather than changes in layer morphology. The demonstrated compatibility of polymer solar cells using solution‐processed photoactive layer and interfacial layers with large area indicates that the introduction of a standard active area of 1 cm² for measuring efficiency of organic record solar cells is feasible. However electric standards for indium tin oxides (ITO) or alternative transparent electrodes need to be developed so that performance of new photovoltaic materials can be compared at square centimeter‐size.     

RGD/FA双靶纳米金棒的制备及其在肿瘤细胞协同靶向成像与光热治疗中的应用

目的:通过制备RGD/FA双靶纳米金考察其与高表达整合素与叶酸受体B16细胞的协同靶向成像与热疗作用;方法:采用功能化PEG分子将靶向小分子RGD与叶酸通过强健Au-S键连接至纳米金棒表面,利用激光共聚焦与808 nm近红外激光器评价修饰纳米金的协同靶向作用;结果:RGD与叶酸分子被成功连接于纳米金表面,且双靶纳米金对小鼠黑色素瘤细胞具有较好的协同靶向作用;结论:同时靶向同一肿瘤细胞的不同表位,可克服单一靶向功能化纳米粒子难以在肿瘤位点有效积累的问题,本研究为多功能纳米金棒在临床肿瘤早期诊断与光热治疗中的应用提供研究基础。     

16.1% Efficient Hysteresis‐Free Mesostructured Perovskite Solar Cells Based on Synergistically Improved ZnO Nanorod Arrays

Significant efficiency improvements are reported in mesoscopic perovskite solar cells based on the development of a low‐temperature solution‐processed ZnO nanorod (NR) array exhibiting higher NR aspect ratio, enhanced electron density, and substantially reduced work function than conventional ZnO NRs. These features synergistically result in hysteresis‐free, scan‐independent, and stabilized devices with an efficiency of 16.1%. Electron‐rich, nitrogen‐doped ZnO (N:ZnO) NR‐based electron transporting materials (ETMs) with enhanced electron mobility produced using ammonium acetate show consistently higher efficiencies by one to three power points than undoped ZnO NRs. Additionally, the preferential electrostatic interaction between the ­nonpolar facets of N:ZnO and the conjugated polyelectrolyte polyethylenimine (PEI) has been relied on to promote the hydrothermal growth of high aspect ratio NR arrays and substantially improve the infiltration of the perovskite light absorber into the ETM. Using the same interactions, a conformal PEI coating on the electron‐rich high aspect ratio N:ZnO NR arrays is ­successfully applied, resulting in a favorable work function shift and altogether leading to the significant boost in efficiency from <10% up to >16%. These results largely surpass the state‐of‐the‐art PCE of ZnO‐based perovskite solar cells and highlight the benefits of synergistically combining mesoscale control with doping and surface modification.