Effects of Electrospinning Parameters on the Microstructure of PVP/TiO2 Nanofibers

Titanium dioxide has excellent chemical, electrical, and optical properties, as well as good chemical stability. For that reason, it is widely used in many fields of study and industry, such as photocatalysts, organic solar cells, sensors, dental implants, and other applications. Many nanostructures of TiO2 have been reported, and electrospinning is an efficient practical technique that has a low cost and high efficiency. In various studies on improving performance, the researchers created nanofibers with suitable microstructures by changing various properties and the many process parameters that can be controlled. In this study, PVP/TiO2 nanofibers were fabricated by the electrospinning process. The diameters of the nanofibers were controlled by various parameters. To understand the effects on the diameter of the nanofibers, various process parameters were controlled: the molecular weight and concentration of the polymers, deionized water, applied voltage, fluid velocity, and concentration of titanium precursor. The average diameter of the PVP nanofibers was controlled in a range of 42.3 nm to 633.0 nm. The average diameter of the PVP/TiO2 nanofibers was also controlled in a range of 63.5 nm to 186.0 nm after heat treatment.

Download Full-text

Electrospinning process parameters dependent investigation of TiO2 nanofibers

Results in Physics ◽

10.1016/j.rinp.2018.08.054 ◽

2018 ◽

Vol 11 ◽

pp. 223-231 ◽

Cited By ~ 14

Author(s):

M.V. Someswararao ◽

R.S. Dubey ◽

P.S.V. Subbarao ◽

Shyam Singh

Keyword(s):

Process Parameters ◽

Electrospinning Process ◽

Tio2 Nanofibers

Download Full-text

Synthesis and characterization of high-efficiency low-cost solar cell thin film

Materials Science-Poland ◽

10.2478/msp-2019-0005 ◽

2019 ◽

Vol 37 (1) ◽

pp. 127-135 ◽

Cited By ~ 1

Author(s):

W. Christopher Immanuel ◽

S. Paul Mary Deborrah ◽

S.S.R. Inbanathan ◽

D. Nithyaa Sree

Keyword(s):

Thin Films ◽

Optical Properties ◽

Solar Cell ◽

High Efficiency ◽

Light Emitting Diode ◽

Uv Spectroscopy ◽

Low Cost ◽

Vital Role ◽

Electrical And Optical Properties ◽

Group Ii Vi Semiconductors

AbstractPolycrystalline chalcogenide semiconductors play a vital role in solar cell applications due to their outstanding electrical and optical properties. Among the chalcogenide semi-conductors, CdZnS is one kind of such important material for applications in various modern solid state devices such as solar cells, light emitting diode, detector etc. Due to their applications in numerous electro-optic devices, group II-VI semiconductors have been studied extensively. In recent years, major attention has been given to the study of electrical and optical properties of CdZnS thin films. In this work, Cd1−xZnxS thin films were prepared by chemical bath deposition technique. Phase purity and surface morphology properties were analyzed using field emission scanning electron microscope (FE-SEM) and X-ray diffraction (XRD) studies. Chemical composition was studied using energy dispersive spectrophotometry (EDS). Optical band gap property was investigated using UV-Spectroscopy. Electrical conductivity studies were performed by two probe method and thermoelectric power setup (TEP) to determine the type of the material. This work reports the effect of Zn on structural, electrical, microstructural and optical properties of these films.

Download Full-text

OPTIMIZATION OF ELECTROSPINNING PROCESS PARAMETERS FOR TISSUE ENGINEERING SCAFFOLDS

Biophysical Reviews and Letters ◽

10.1142/s1793048006000148 ◽

2006 ◽

Vol 01 (02) ◽

pp. 153-178 ◽

Cited By ~ 25

Author(s):

MING CHEN ◽

PRABIR K. PATRA ◽

STEVEN B. WARNER ◽

SANKHA BHOWMICK

Keyword(s):

Cell Growth ◽

Process Parameters ◽

Growth Kinetics ◽

Fiber Diameter ◽

Average Diameter ◽

Solution Concentration ◽

Electrospinning Process ◽

Average Fiber Diameter ◽

High Concentration ◽

Cell Growth Kinetics

The goal of the current study was to optimize important process parameters for electrospinning polycaprolactone (PCL) for growing 3T3 fibroblasts. We hypothesized that the smallest obtainable fiber diameter would provide the best cell growth kinetics and we tested this hypothesis for three different process parameters: solution concentration, voltage and collector screen distance. Beaded structures were formed when using low concentration electrospinning solutions (8 wt% to 13 wt%), in which the viscosity ranged from 16.0 c P to 340.0 c P . In this concentration range, cell growth kinetics was impeded when using a high concentration of cells (8–10 × 105). Higher PCL concentration led to an increase in the average fiber diameter from 400 nm to 1600 nm when PCL solution concentration changed from 15 wt% to 20 wt%. Although, the mean values indicated that cell growth kinetics were higher at the lower end of the concentration (15% as opposed to 20%) and this correlated with lower average fiber diameter, the results in this range were not statistically significant (p > 0.05). The average fiber diameter of scaffolds first decreased and then increased when electrospinning voltage was increased. The cell growth kinetics demonstrated that smaller average diameter PCL fiber scaffolds had higher growth kinetics than larger average diameter scaffolds with the best conditions obtained at 15 KV. By increasing the screen distance, the average fiber diameter decreased but had no significant impact on cell growth kinetics. In summary, the optimal parametric space for 3T3 fibroblast growth for our studies was electrospinning a 15 wt% PCL solution using 15 kV voltage and a 25 cm collector distance.

Download Full-text

Fast Generation of Micro-Channels on Cylindrical Surfaces by Elliptical Vibration Texturing

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4027126 ◽

2014 ◽

Vol 136 (4) ◽

Cited By ~ 23

Author(s):

Ping Guo ◽

Yong Lu ◽

Pucheng Pei ◽

Kornel F. Ehmann

Keyword(s):

Process Parameters ◽

High Efficiency ◽

Low Cost ◽

Pattern Generation ◽

Depth Of Cut ◽

Channel Formation ◽

Structured Surfaces ◽

Elliptical Vibration ◽

Micro Channels ◽

Elliptical Vibration Texturing

Micro-structured surfaces are assuming an ever-increasing role since they define the ultimate performance of many industrial components and products. Micro-channels, in particular, have many potential applications in micro-fluidic devices, micro heat exchangers, and friction control. This paper proposes an innovative vibration-assisted machining method to generate micro-channels on the external surface of a cylinder. This method, referred to as elliptical vibration texturing, was originally developed by the authors to generate dimple patterns. It uses the modulation of the depth-of-cut by tool vibrations to create surface textures. The most promising features of the proposed method are its high efficiency, low cost, and scalability for mass production. It is shown that with proper combinations of the process parameters the created dimples start to overlap and form channels. An analytical model is established to predict channel formation with respect to the overlapping ratios of the dimples. Channel formation criteria and expressions for channel geometries are given along with a channel generation map that relates channel geometry to the process parameters. Experimental results are given to verify the model. A further example of micro-pattern generation is also given to showcase the flexibility of the process.

Download Full-text

Strategically Integrating Quantum Dots into Organic and Perovskite Solar Cells

Journal of Materials Chemistry A ◽

10.1039/d0ta11336k ◽

2021 ◽

Author(s):

Ming Chen ◽

Jiuxing Wang ◽

Feifei Yin ◽

Zhonglin Du ◽

Laurence A Belfiore ◽

...

Keyword(s):

Quantum Dots ◽

Solar Cells ◽

Organic Solar Cells ◽

High Efficiency ◽

Low Cost ◽

Perovskite Solar Cells ◽

Photovoltaic Devices

Urgent requirements for high-efficiency and low-cost photovoltaic devices are constantly pushing forward the development of the emerging solar cells. Currently, organic solar cells (OSCs) and perovskites solar cells (PSCs) were...

Download Full-text

Hybrid Materials for Solar Cells

Materials Research Foundations - Materials for Solar Cell Technologies II ◽

10.21741/9781644901410-7 ◽

2021 ◽

pp. 149-174

Author(s):

U. Fegade

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Organic Solar Cells ◽

High Efficiency ◽

Low Cost ◽

Dye Sensitized Solar Cells ◽

Space Applications ◽

Tandem Solar Cells ◽

Low Efficiency ◽

Sensitized Solar Cells

Solar energy is an attractive renewable energy source across the globe that can help overcome the energy crises and has the ability to replace conventional resources. Hybrid solar cells have higher conversion efficiency. In the current chapter the research related to the carbon nanotubes, organic and inorganic solar cell, dye-sensitized solar cells and tandem solar cells are reviewed. The organic solar cells are most suitable and economic, but it has low efficiency of up to 15%. The inorganic solar cells are very expensive and have high efficiency of up to 46% and are used in space applications. The hybrid solar cell is the third type and the perovskite tandem has already proven to be quite efficient (17%) and low cost, mostly because of the cheap materials that are being used.

Download Full-text

The Essence and Efficiency Limits of Bulk-Heterostructure Organic Solar Cells

MRS Proceedings ◽

10.1557/opl.2012.750 ◽

2012 ◽

Vol 1390 ◽

Cited By ~ 1

Author(s):

M. Alam ◽

B. Ray ◽

M. Khan ◽

S. Dongaonkar

Keyword(s):

Organic Solar Cells ◽

Carrier Transport ◽

High Efficiency ◽

Bulk Heterojunction ◽

Low Cost ◽

Short Circuit ◽

Short Circuit Current ◽

Substantial Improvement ◽

Open Circuit ◽

Future Improvement

Abstract:Since its introduction in early 1990s, bulk-heterojunction organic photovoltaic solar cell (BHJ-OPV) has promised high-efficiency at ultra-low cost and weight, with potential for non-traditional applications such as building-integrated PV. There is a widespread presumption, however, that the complexity of morphology makes carrier transport in OPV irreducibly complicated, and possibly, beyond predictive modeling. In this paper, we use elementary and intuitive arguments to derive the fundamental thermodynamic as well as morphology-specific practical limits of BHJ-OPV efficiency. We find that constraints of the percolation threshold and trade-off among short-circuit current, open circuit voltage, and fill factor make substantial improvement in OPV efficiency difficult. We posit that future improvement in OPV will rely not on morphology engineering, or reducing the polymer bandgap, but on increasing both the effective μ × τ product and the cross-gap between donor/acceptors. Even if the OPV fails to achieve the highest efficiency anticipated by the thermodynamic limit, its novel form factor, lightweight, and transparency can make it a commercially viable option for many applications.

Download Full-text

Toward Low-Cost, High-Efficiency, and Scalable Organic Solar Cells with Transparent Metal Electrode and Improved Domain Morphology

IEEE Journal of Selected Topics in Quantum Electronics ◽

10.1109/jstqe.2010.2044634 ◽

2010 ◽

Vol 16 (6) ◽

pp. 1807-1820 ◽

Cited By ~ 52

Author(s):

Myung-Gyu Kang ◽

Hui Joon Park ◽

Se Hyun Ahn ◽

Ting Xu ◽

L. Jay Guo

Keyword(s):

Solar Cells ◽

Organic Solar Cells ◽

High Efficiency ◽

Low Cost ◽

Metal Electrode

Download Full-text

Fast High Order Large Eddy Simulations on Many Core Computing Systems for Turbomachinery

Volume 2D: Turbomachinery ◽

10.1115/gt2016-57468 ◽

2016 ◽

Cited By ~ 2

Author(s):

Yi Lu ◽

Kai Liu ◽

W. N. Dawes

Keyword(s):

Turbine Blade ◽

High Efficiency ◽

Low Cost ◽

Time Integration ◽

Computing System ◽

High Order ◽

Computing Resource ◽

The Many ◽

Many Core ◽

Key Techniques

The overall aim of our research is to enable overnight high fidelity LES for realistic industry problems on affordable computing resource. We have adopted a “3E” approach: high spatial discretization Efficiency on general unstructured meshes, high Efficiency accurate time integration and high computing Efficiency on modern low cost HPC hardware. Our approach is centered on high order Flux Reconstruction with local time stepping — the STEFR algorithm [1]. In this paper, an offload-mode version of this code is described targeted at a heterogeneous many-core computing system based on low cost commodity hardware — Intel PHI cards. Three key techniques are introduced to achieve high FLOP rates — and optimal usage of non-equilibrium memory of both CPU and the many core coprocessor — with three levels of parallelization, multi-level nonequilibrium mesh partition and an asynchronous computing structure. A series of high order LES runs for a high lift low pressure turbine blade and a transonic turbine blade, with different order of accuracy, both fully wall-resolved and wall-modelled, were performed, analyzed and presented. This work demonstrates that the high order STEFR method has the potential to support over-night LES for realistic industrial problems on affordable computing resource.

Download Full-text