Realization of ordered magnetic skyrmions in thin films at ambient conditions

Natural evaporation has recently come under consideration as a viable source of renewable energy. Demonstrations of the validity of the concept have been reported for devices incorporating carbon-based nanocomposite materials. In this study, we investigated the possibility of using polymer thin films to generate electricity from natural evaporation. We considered a polymeric system based on polyvinylidene fluoride (PVDF). Porous PVDF films were created by incorporating a variety of nanocomposite materials into the polymer structure through a simple mixing procedure. Three nanocomposite materials were considered: carbon nanotubes, graphene oxide, and silica. The evaporation-induced electricity generation was confirmed experimentally under various ambient conditions. Among the nanocomposite materials considered, mesoporous silica (SBA-15) was found to outperform the other two materials in terms of open-circuit voltage, and graphene oxide generated the highest short-circuit current. It was found that the nanocomposite material content in the PVDF film plays an important role: on the one hand, if particles are too few in number, the number of channels will be insufficient to support a strong capillary flow; on the other hand, an excessive number of particles will suppress the flow due to excessive water absorption underneath the surface. We show that the device can be modeled as a simple circuit powered by a current source with excellent agreement between the theoretical predictions and experimental data.

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Tetrabutylammonium cations for moisture-resistant and semitransparent perovskite solar cells

Journal of Materials Chemistry A ◽

10.1039/c7ta06735f ◽

2017 ◽

Vol 5 (42) ◽

pp. 22325-22333 ◽

Cited By ~ 25

Author(s):

Isabella Poli ◽

Salvador Eslava ◽

Petra Cameron

Keyword(s):

Thin Films ◽

Solar Cells ◽

Perovskite Solar Cells ◽

Ambient Conditions ◽

The Stability ◽

Moisture Resistant

Tetra-butylammonium cations have been partially substituted for methylammonium cations in perovskite thin films. The stability of devices stored under ambient conditions was enhanced by the presence of TBA and cells with high mol% TBA were found to have reasonable efficiencies while being semi-transparent.

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Improved Morphology of Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate) Thin Films for All-Electrospray-Coated Organic Photovoltaic Cells

Advances in Materials Science and Engineering ◽

10.1155/2016/9734854 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Yingjie Liao ◽

Takeshi Fukuda ◽

Norihiko Kamata

Keyword(s):

Thin Films ◽

High Performance ◽

Photovoltaic Cells ◽

Spray Coating ◽

Organic Photovoltaic ◽

Organic Photovoltaic Cells ◽

Ambient Conditions ◽

Deposition Parameters ◽

Coating Methods ◽

Organic Devices

Spray coating technique has been established as a promising substitute for the traditional coating methods in the fabrication of organic devices in many reports recently. Control of film morphology at the microscopic scale is critical if spray-coated devices are to achieve high performance. Here we investigate electrospray deposition protocols for the fabrication of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) thin films with a single additive system under ambient conditions at room temperature. Critical deposition parameters including solution composition, applied voltage, and relative humidity are discussed systematically. Optimized process for preparing homogenous PEDOT:PSS thin films is applied to all-electrospray-coated organic photovoltaic cells and contributes to a power conversion efficiency comparable to that of the corresponding all-spin-coated device.

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Enhanced Grain-boundary Emission Lifetime and Additive Induced Crystal Orientation in One-Step Spin-Coated Mixed Cationic (FA/MA) Lead Perovskite Thin Films Stabilized by Zinc Iodide Doping

10.26434/chemrxiv.5484073.v1 ◽

2017 ◽

Author(s):

René M. Williams ◽

Loreta A. Muscarella ◽

Dina Petrova ◽

Rebecca Jorge Cervasio ◽

Aram Farawar ◽

...

Keyword(s):

Thin Films ◽

Laser Scanning ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Crystal Formation ◽

Ambient Conditions ◽

Emission Lifetime ◽

Photoluminescence Lifetime ◽

One Step ◽

Zinc Iodide

Mixed cationic lead perovskites containing formamidinium and methylammonium can be stabilized by incorporating ZnI<sub>2 </sub>as an “internal desiccant”. Next to prolonged stability under ambient conditions we show with XRD that the use of an additive, 3-chloropropyl ammonium chloride, influences crystal formation by orienting the crystals. These ~500 nm crystals show individual photoluminescent behavior in thin films and have a longer photoluminescence lifetime at the grain boundaries as compared to the center of the crystal or relative to un-doped materials without the additive made under identical conditions. Charges recombine slower at the edges of the crystals as observed with confocal laser scanning microscopy

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Thin films of copper phthalocyanine deposited by solution processing methods

Materials Science-Poland ◽

10.2478/msp-2020-0007 ◽

2020 ◽

Vol 38 (1) ◽

pp. 79-90

Author(s):

Hubert Gojzewski ◽

Fatemeh Ghani ◽

Mirosław Szybowicz

Keyword(s):

Thin Films ◽

Copper Phthalocyanine ◽

Substrate Surface ◽

Spray Coating ◽

Solution Concentration ◽

Dip Coating ◽

Solution Processing ◽

Ambient Conditions ◽

Processing Methods ◽

Main Technique

AbstractIn this work, we show and discuss the surface structure picture of copper phthalocyanine (CuPc) thin films deposited from trifluoroacetic acid (TFA) solvent onto silicon substrates at ambient conditions by four solution processing methods, namely drop-casting, dip-coating, spin-casting and spray-coating. The CuPc films were studied by AFM, as the main technique, and complemented by micro-Raman spectroscopy. Essentially, such thin films consist of CuPc molecular nanoribbons of a fixed ~1 nm thickness. CuPc molecules are arranged in an in-plane direction and formed in stacks under a defined tilt angle with respect to the substrate surface (monolayer) or underlying CuPc layer (multilayer). The film morphology takes various forms depending on the solution concentration, number of layers, and the deposition method. For instance, the morphology varies from very wide (~600 nm) but flat (~1 nm) ribbons for films prepared by dip-coating to crystallized rod-like features (multi-layered ribbons) when obtained by spray-coating. The factors studied in this paper should be taken into consideration in designing and controlling the criteria for rigorous CuPc film architecture.

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Magnetic Skyrmions in Thin Films

Springer Series in Solid-State Sciences - Topology in Magnetism ◽

10.1007/978-3-319-97334-0_4 ◽

2018 ◽

pp. 117-150 ◽

Cited By ~ 1

Author(s):

Gong Chen

Keyword(s):

Thin Films ◽

Magnetic Skyrmions

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Phase Transformations in Sol-Gel PZT Thin Films

MRS Proceedings ◽

10.1557/proc-623-185 ◽

2000 ◽

Vol 623 ◽

Cited By ~ 1

Author(s):

D.P. Eakin ◽

M.G. Norton ◽

D.F. Bahr

Keyword(s):

Thin Films ◽

Heat Treatment ◽

Room Temperature ◽

Structural Changes ◽

Sol Gel ◽

Ex Situ ◽

Ambient Conditions ◽

Crystalline Films ◽

In Situ Heating

AbstractThin films of PZT were deposited onto platinized and bare single crystal NaCl using spin coating and sol-gel precursors. These films were then analyzed using in situ heating in a transmission electron microscope. The results of in situ heating are compared with those of an ex situ heat treatment in a standard furnace, mimicking the heat treatment given to entire wafers of these materials for use in MEMS and ferroelectric applications. Films are shown to transform from amorphous to nanocrystalline over the course of days when held at room temperature. While chemical variations are found between films crystallized in ambient conditions and films crystallized in the vacuum conditions of the microscope, the resulting crystal structures appear to be insensitive to these differences. Significant changes in crystal structure are found at 500°C, primarily the change from largely amorphous to the beginnings of clearly crystalline films. Crystallization does occur over the course of weeks at room temperature in these films. Structural changes are more modest in these films when heated in the TEM then those observed on actual wafers. The presence of Pt significantly influences both the resulting structure and morphology in both in situ and ex situ heated films. Without Pt present, the films appear to form small, 10 nm grains consisting of both cubic and tetragonal phases, whereas in the case of the Pt larger, 100 nm grains of a tetragonal phase are formed.

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Optical and Morphological Studies of Thermally Evaporated PTCDI-C8 Thin Films for Organic Solar Cell Applications

International Journal of Photoenergy ◽

10.1155/2013/205105 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 9

Author(s):

Ronak Rahimi ◽

V. Narang ◽

D. Korakakis

Keyword(s):

Thin Films ◽

Silicon Substrates ◽

High Electron ◽

Ambient Conditions ◽

Force Microscopy ◽

Morphological Studies ◽

Atomic Force ◽

Organic Semiconductor Devices ◽

Thermal Evaporator ◽

High Degree

PTCDI-C8 due to its relatively high photosensitivity and high electron mobility has attracted much attention in organic semiconductor devices. In this work, thin films of PTCDI-C8 with different thicknesses were deposited on silicon substrates with native silicon dioxide using a vacuum thermal evaporator. Several material characterization techniques have been utilized to evaluate the structure, morphology, and optical properties of these films. Their optical constants (refractive index and extinction coefficient) have been extracted from the spectroscopic ellipsometry (SE). X-ray reflectivity (XRR) and atomic force microscopy (AFM) were employed to determine the morphology and structure as well as the thickness and roughness of the PTCDI-C8 thin films. These films revealed a high degree of structural ordering within the layers. All the experimental measurements were performed under ambient conditions. PTCDI-C8 films have shown to endure ambient condition which allows pots-deposition characterization.

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Electrochemical preparation of few layer-graphene nanosheets via reduction of oriented exfoliated graphene oxide thin films in acetamide–urea–ammonium nitrate melt under ambient conditions

Thin Solid Films ◽

10.1016/j.tsf.2010.11.019 ◽

2011 ◽

Vol 519 (7) ◽

pp. 2323-2327 ◽

Cited By ~ 28

Author(s):

V.S. Dilimon ◽

S. Sampath

Keyword(s):

Thin Films ◽

Graphene Oxide ◽

Ammonium Nitrate ◽

Graphene Nanosheets ◽

Ambient Conditions ◽

Electrochemical Preparation ◽

Layer Graphene ◽

Exfoliated Graphene ◽

Urea Ammonium Nitrate ◽

Few Layer Graphene

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Nanostructured Ceramic Thin Films and Membranes by Wet Chemical Processing Methods

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.1252 ◽

2006 ◽

Vol 45 ◽

pp. 1252-1259

Author(s):

Jing Yu Shi ◽

Matthew L. Mottern ◽

Krenar Shqau ◽

Henk Verweij

Keyword(s):

Thin Films ◽

Colloidal Stability ◽

Synthesis Process ◽

Narrow Particle Size Distribution ◽

Chemical Processing ◽

Organic Additives ◽

Ambient Conditions ◽

Ceramic Thin Films ◽

Nanostructured Ceramic ◽

Wet Chemical

Nanostructured ceramic thin films and membranes are used for protective or functional purposes and prepared on dense or porous substrate materials. Wet chemical methods enable cheap, low-temperature, mass-scale manufacturing routes. They produce fine-grained porous and dense micro-structures that cannot be realized otherwise. In wet-chemical processing, clean nanoparticle dispersions are deposited on the substrate at, primarily, ambient conditions. The deposition is followed by a (rapid) thermal processing treatment to remove liquids and organic additives, to convert precursors to the target composition, and to establish the final porous and dense micro-structure. In the synthesis of precursor dispersions it is very important to obtain nanoparticles with a near-isometric shape and a fairly narrow particle size distribution, without the formation of secondary (agglomerate) structures. In particular the latter requires careful control of solution and interfacial chemistry to achieve proper colloidal stability, during and after the synthesis process. Characterization of coating integrity, defect morphology and defect population is done by decoration methods, microscopy, ellipsometry and statistical methods that employ membrane transport properties.

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