Study of solvent effect on structural and photoconductive behavior of ternary chalcogenides InBiS3-In2S3-Bi2S3 composite thin films deposited via AACVD

Abstract In the present work ternary composite InBiS3-In2S3-Bi2S3 (IBS) thin films are developed using a homogeneous mixture of precursors [Bi(S2CN(C2H5)2)3]2 (1) and [In(S2CNCy2)3]‧2py (2), separately in toluene and chloroform solutions at 500°C under an inert atmosphere of argon gas via aerosol assisted chemical vapor deposition (AACVD) technique. The phase purity, chemical composition and morphological study of both the films deposited from toluene and chloroform solutions are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and Field emission scanning electron microscopy (FESEM). The surface morphology showed rod like structure of the films developed from toluene while the films grown from chloroform solution give flake like shapes. The UV-visible spectroscopy explicated that the thin films developed from toluene and chloroform solutions show wide range absorption in whole visible region. Linear Scan voltammetry results show that both the films give negligible dark current, however, the films fabricated from toluene solution give a sharp steep curve with maximum photocurrent density of 2.3 mA‧cm-2 at 0.75 V vs Ag/AgCl/3M KCl using 0.05 M sodium sulphide solution under AM 1.5 G illumination (100 mW‧cm-2), while the film grown from chloroform generates a photocurrent density of 2.1 mA‧cm-2 under similar conditions. The LSV outcomes are further supported by electrochemical impedance spectroscopy (EIS) that gives charge transfer resistance (Rct) value of 8,571 Ω for the films developed from toluene as compared to films fabricated from chloroform with Rct value of 12,476 Ω.

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Fabrication, characterization, and photocatalytic performance of ternary cadmium chalcogenides CdIn2S4 and Cd7.23Zn2.77S10-ZnS thin films

Main Group Metal Chemistry ◽

10.1515/mgmc-2021-0008 ◽

2020 ◽

Vol 44 (1) ◽

pp. 39-50

Author(s):

Umar Daraz ◽

Tariq Mahmood Ansari ◽

Shafique Ahmad Arain ◽

Muhammad Adil Mansoor ◽

Muhammad Mazhar ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Chemical Vapor ◽

Linear Sweep Voltammetry ◽

Photocurrent Density ◽

Charge Transfer Resistance ◽

Single Step ◽

Transfer Resistance ◽

X Ray ◽

Dual Source

Abstract Dithiocarbamate complexes [Cd(S2CNCy2)2(py)] (1), [In(S2CNCy2)3]·2py (2) and [Zn(S2CNCy2)2(py)] (3) were synthesized and toluene solution of (1) and (2) was used as dual source precursor for the synthesis of CdIn2S4 (CIS), while that of (1) and (3) was applied for the deposition of Cd7.23Zn2.77S10–ZnS composite (CZS-ZS) thin film photoan-odes by employing single step aerosol assisted chemical vapor deposition (AACVD) technique. Deposition experiments were performed at 500°C under an inert ambient of argon gas. The structural properties of deposited films were evaluated by using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. The field emission scanning electron microscopy (FESEM) exposed surface morphologies while UV-Visible spectrophotometry revealed that CIS is low band gap photoanode in comparison to CZS-ZS. The comparison of photoelectrochemical (PEC) responses measured in identical conditions in terms of linear sweep voltammetry (LSV) depicts photocurrent density of 4.4 mA /cm2 and 2.9 mA/cm2 at applied potential of 0.7 V under solar light intensity of 100 mW/cm2 for CIS and CZS-ZS respectively. Further, electrochemical impedance spectroscopy (EIS) confirms that PEC properties of CIS are superior to CZS-ZS photoanode as the former offer less charge transfer resistance (Rct) 0.03 MΩ in comparison to CZS-ZS having Rct value of 0.06 MΩ.

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From Allergens to Battery Anodes: Nature-Inspired, Pollen Derived Carbon Architectures for Room- and Elevated- Temperature Li-ion Storage

Scientific Reports ◽

10.1038/srep20290 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 22

Author(s):

Jialiang Tang ◽

Vinodkumar Etacheri ◽

Vilas G. Pol

Keyword(s):

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Lithium Ion ◽

Charge Transfer Resistance ◽

High Rate ◽

Energy Storage Devices ◽

Lithium Storage ◽

Transfer Resistance ◽

Carbonaceous Particles ◽

X Ray

Abstract The conversion of allergic pollen grains into carbon microstructures was carried out through a facile, one-step, solid-state pyrolysis process in an inert atmosphere. The as-prepared carbonaceous particles were further air activated at 300 °C and then evaluated as lithium ion battery anodes at room (25 °C) and elevated (50 °C) temperatures. The distinct morphologies of bee pollens and cattail pollens are resembled on the final architecture of produced carbons. Scanning Electron Microscopy images shows that activated bee pollen carbon (ABP) is comprised of spiky, brain-like and tiny spheres; while activated cattail pollen carbon (ACP) resembles deflated spheres. Structural analysis through X-ray diffraction and Raman spectroscopy confirmed their amorphous nature. X-ray photoelectron spectroscopy analysis of ABP and ACP confirmed that both samples contain high levels of oxygen and small amount of nitrogen contents. At C/10 rate, ACP electrode delivered high specific lithium storage reversible capacities (590 mAh/g at 50 °C and 382 mAh/g at 25 °C) and also exhibited excellent high rate capabilities. Through electrochemical impedance spectroscopy studies, improved performance of ACP is attributed to its lower charge transfer resistance than ABP. Current studies demonstrate that morphologically distinct renewable pollens could produce carbon architectures for anode applications in energy storage devices.

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Nanostructured β−NiS Catalyst for Enhanced and Stable Electro−oxidation of Urea

Catalysts ◽

10.3390/catal10111280 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1280

Author(s):

Tzu-Ho Wu ◽

Yan-Cheng Lin ◽

Bo-Wei Hou ◽

Wei-Yuan Liang

Keyword(s):

Photoelectron Spectroscopy ◽

Electrochemical Impedance ◽

Hydrothermal Reaction ◽

Charge Transfer Resistance ◽

Hydrogen Energy ◽

Transfer Resistance ◽

X Ray ◽

Onset Potential ◽

Slow Kinetics ◽

Electro Oxidation

Urea oxidation reaction (UOR) has received a high level of recent interest since electrochemical oxidation of urea can remediate harmful nitrogen compounds in wastewater and accomplish hydrogen fuel production simultaneously. Thus, urea is considered to be potential hydrogen energy source that is inherently safe for fuel cell applications. However, the catalytic reaction suffers from slow kinetics due to six electron transfer in UOR. In this work, β phase NiS is successfully prepared through facile hydrothermal reaction, in which diethanolamine (DEA) was added as chelating agent leading to 3D nanoflower morphology. The crystal structure, surface morphology, and chemical bonding of the β−NiS were characterized by X–ray diffraction (XRD), scanning electron microscope (SEM), and X−ray photoelectron spectroscopy (XPS), respectively. The UOR performance of NiS was evaluated by means of linear sweep voltammetry (LSV), Tafel analysis, electrochemical impedance spectroscopy (EIS), chronoamperometry, and chronopotentiometry in 1 M KOH electrolyte containing 0.33 M urea. Compared to the Ni(OH)2 counterpart, NiS exhibits lower onset potential, increased current responses, faster kinetics of urea oxidation, lower charge transfer resistance, and higher urea diffusion coefficient, leading to the enhanced catalytic performance toward UOR. Moreover, the developed NiS catalyst exhibits superior stability and tolerance towards urea electro−oxidation in 10,000 s test.

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Preparation of novel Ti-based MnOx electrodes by spraying method for electrochemical oxidation of Acid Red B

Water Science & Technology ◽

10.2166/wst.2019.282 ◽

2019 ◽

Vol 80 (2) ◽

pp. 365-376

Author(s):

Xuelu Xu ◽

Jiao Zhao ◽

Subei Bai ◽

Rongrong Mo ◽

Yan Yang ◽

...

Keyword(s):

Electrochemical Oxidation ◽

Photoelectron Spectroscopy ◽

Manganese Oxides ◽

Electrochemical Impedance ◽

Charge Transfer Resistance ◽

Cell Potential ◽

Transfer Resistance ◽

X Ray ◽

Concentration Changes ◽

Spraying Method

Abstract At different calcination conditions, titanium-based manganese oxides (MnOx) electrodes were fabricated by spraying method without adhesive. The MnOx/Ti electrodes were applied in electrochemical oxidation of wastewater treatment for the first time. The surface morphologies of electrodes were tested by scanning electron microscopy. The formation of different manganese oxidation states on electrodes was confirmed by X-ray diffraction and X-ray photoelectron spectroscopy. The electrochemical properties of the electrodes have been performed by means of cyclic voltammetry and electrochemical impedance spectroscopy. The characterizations revealed that the MnOx/Ti-350(20) electrode, prepared at calcination temperature of 350 °C for 20 min, exhibited fewer cracks on the electrode surface, larger electrochemically effective surface area and lower charge transfer resistance than electrodes prepared at other calcination conditions. Moreover, Acid Red B was used as target pollutant to test the electrode activity via monitoring the concentration changes by UV spectrophotometer. The results showed that the MnOx/Ti-350(20) electrode presented the best performance on decolorization of Acid Red B with the lowest cell potential during the process of electrochemical oxidation, and the chemical oxygen demand (COD) conversion was 50.7%. Furthermore, the changes of Acid Red B during the electrochemical oxidation process were proposed by the UV–vis spectra.

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Influence of HAP on the Morpho-Structural Properties and Corrosion Resistance of ZrO2-Based Composites for Biomedical Applications

Crystals ◽

10.3390/cryst11020202 ◽

2021 ◽

Vol 11 (2) ◽

pp. 202

Author(s):

Réka Barabás ◽

Carmen Ioana Fort ◽

Graziella Liana Turdean ◽

Liliana Bizo

Keyword(s):

Electrochemical Impedance ◽

Artificial Saliva ◽

Synergetic Effect ◽

Composite Layer ◽

Charge Transfer Resistance ◽

Processing Route ◽

Dental Alloys ◽

Metallic Electrode ◽

Transfer Resistance ◽

X Ray

In the present work, ZrO2-based composites were prepared by adding different amounts of antibacterial magnesium oxide and bioactive and biocompatible hydroxyapatite (HAP) to the inert zirconia. The composites were synthesized by the conventional ceramic processing route and morpho-structurally analyzed by X-ray powder diffraction (XRPD) and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). Two metallic dental alloys (i.e., Ni–Cr and Co–Cr) coated with a chitosan (Chit) membrane containing the prepared composites were exposed to aerated artificial saliva solutions of different pHs (i.e., 4.3, 5, 6) and the corrosion resistances were investigated by electrochemical impedance spectroscopy technique. The obtained results using the two investigated metallic dental alloys shown quasi-similar anticorrosive properties, having quasi-similar charge transfer resistance, when coated with different ZrO2-based composites. This behavior could be explained by the synergetic effect between the diffusion process through the Chit-composite layer and the roughness of the metallic electrode surface.

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Effect of Zirconium Oxide Reinforcement on Microstructural, Electrochemical and Mechanical Properties of TiNi Alloy Produced Via Powder Metallurgy Route

Journal of Engineering Materials and Technology ◽

10.1115/1.4051308 ◽

2021 ◽

pp. 1-22

Author(s):

Syed Abbas Raza ◽

Muhammad Imran Khan ◽

Muhammad Ramzan Abdul karim ◽

Rashid Ali ◽

Muhammad Umair Naseer ◽

...

Keyword(s):

Electrochemical Impedance ◽

Passive Layer ◽

Charge Transfer Resistance ◽

Tini Alloy ◽

X Ray Diffraction ◽

Zro2 Content ◽

Transfer Resistance ◽

X Ray ◽

Conventional Sintering ◽

Layer Resistance

Abstract Equiatomic TiNi alloy composites, reinforced with 0, 5, 10 and 15 vol. % ZrO2, were synthesized using conventional sintering approach. Equiatomic TiNi pre-alloyed powder and ZrO2 powder were mixed in planetary ball mill for 6 hours followed by cold compaction and pressure-less sintering, respectively. The sintered density was found to vary inversely with the addition of ZrO2 content. The X-Ray diffraction spectra have shown the formation of multiple-phases which were resulted from the decomposition of the B19'and B2 phases of the equiatomic TiNi alloy due to the addition of ZrO2 and higher diffusion rate of Ni than that of Ti in the alloy composite. An increase in hardness was noted due to the addition of ZrO2, measured by micro and nanoindentation techniques. Potentiodynamic polarization scan revealed a 10% decrease in the corrosion rate of the composite containing 10 vol. % ZrO2. Electrochemical impedance spectroscopy results indicated an increase in passive layer resistance (Rcoat) due to the increase in charge transfer resistance (Rct) caused by the reduced leaching of ions from the surface.

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Growth of Highly Oriented Zinc Oxide Thin Films by Plasma Enhanced Chemical Vapor Deposition

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.321-323.1687 ◽

2006 ◽

Vol 321-323 ◽

pp. 1687-1690 ◽

Cited By ~ 1

Author(s):

Hee Joon Kim ◽

Dong Young Jang ◽

Prem Kumar Shishodia ◽

Akira Yoshida

Keyword(s):

Thin Films ◽

Zinc Oxide ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Visible Region ◽

Chemical Vapor ◽

Zno Films ◽

X Ray ◽

Crystalline Films

In the paper, zinc oxide (ZnO) thin films are deposited by plasma enhanced chemical vapor deposition (PECVD) at different substrate temperatures. The ZnO films are characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The analysis results indicate that highly crystalline films with high orientation can be obtained at a substrate temperature of 300 oC with 50 ml/min flow rate from Diethylzinc (DEZ). Furthermore, the investigation of optical property shows that ZnO films are transparent, and the peak transmittance in the visible region is as high as 85%.

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Croton lechleri Extracts as Green Corrosion Inhibitors of Admiralty Brass in Hydrochloric Acid

Molecules ◽

10.3390/molecules26247417 ◽

2021 ◽

Vol 26 (24) ◽

pp. 7417

Author(s):

Carlos Cevallos-Morillo ◽

Pablo Cisneros-Pérez ◽

Roxana Llive ◽

Marvin Ricaurte ◽

Carlos Reinoso ◽

...

Keyword(s):

Natural Products ◽

Photoelectron Spectroscopy ◽

Surface Characterization ◽

Corrosion Inhibitors ◽

Electrochemical Impedance ◽

Transfer Resistance ◽

X Ray ◽

Chemical Structures ◽

Green Corrosion Inhibitors ◽

Croton Lechleri

Croton lechleri, commonly known as Dragon’s blood, is a tree cultivated in the northwest Amazon rainforest of Ecuador and Peru. This tree produces a deep red latex which is composed of different natural products such as phenolic compounds, alkaloids, and others. The chemical structures of these natural products found in C. lechleri latex are promising corrosion inhibitors of admiralty brass (AB), due to the number of heteroatoms and π structures. In this work, three different extracts of C. lechleri latex were obtained, characterized phytochemically, and employed as novel green corrosion inhibitors of AB. The corrosion inhibition efficiency (IE%) was determined in an aqueous 0.5 M HCl solution by potentiodynamic polarization (Tafel plots) and electrochemical impedance spectroscopy, measuring current density and charge transfer resistance, respectively. In addition, surface characterization of AB was performed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy techniques. Chloroform alkaloid-rich extracts resulted in IE% of 57% at 50 ppm, attributed to the formation of a layer of organic compounds on the AB surface that hindered the dezincification process. The formulation of corrosion inhibitors from C. lechleri latex allows for the valorization of non-edible natural sources and the diversification of the offer of green corrosion inhibitors for the chemical treatment of heat exchangers.

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Structural and Optical Properties of Zn1-XCoXO Thin Films Fabricated by Laser Molecular Beam Epitaxy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.295-297.1958 ◽

2011 ◽

Vol 295-297 ◽

pp. 1958-1963

Author(s):

Jing Zhi Yang ◽

Li Juan Fu ◽

Xiao Peng Qi ◽

Hong Yun Li

Keyword(s):

Thin Films ◽

Molecular Beam Epitaxy ◽

Photoelectron Spectroscopy ◽

Molecular Beam ◽

Ambient Pressure ◽

Visible Region ◽

Hexagonal Structure ◽

Axis Orientation ◽

X Ray ◽

Laser Molecular Beam Epitaxy

Zn1-xCoxO thin films on sapphire (0001) substrates were synthesized by laser molecular beam epitaxy (LMBE) method at various temperatures under a work ambient pressure of 5.0 x 10-5Pa condition. X-ray diffraction (XRD) spectra, UV–visible transmission spectra and X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectra were employed to characterize the properties of samples. All samples were of wurtzite hexagonal structure with the preferential c-axis-orientation. Co2+ions incorporated into ZnO lattice and substituted for Zn2+ions. ZnLMM Auger spectrum implied Zn interstitials existed in sample. The optical transmission of all samples was relatively high in visible region. Two PL emission peaks located at 418 nm and 490 nm were assigned to the electron transition from the Zn interstitials to the top of the valence band and from the Zn interstitials to the Zn vacancies, respectively.

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Multitechnique problem solving using EDS/EPMA and surface analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133540 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1782-1783

Author(s):

Steven J. Simko ◽

Richard A. Waldo

Keyword(s):

Thin Films ◽

Electron Beam ◽

Integrated Circuits ◽

Photoelectron Spectroscopy ◽

Electron Spectroscopy ◽

High Surface ◽

Primary Electron ◽

Sampling Depth ◽

X Ray ◽

Wide Range

Thin films are used in a wide range of modern technologies. Examples include sensors, antiwear coatings, optical coatings, and integrated circuits. A variety of methods have evolved for characterizing thin films in the thickness range of 1 monolayer to several micrometers. Electron probe microanalysis (EPMA) or energy dispersive x-ray spectroscopy (EDS) are two methods for characterizing thicker films (>1 μm). In these techniques, the sampling depth depends on the penetration depth of the primary electron beam which can be controlled by changing the electron beam energy. Thin films can also be characterized using line scans on specimens prepared as polished cross-sections or after angle lapping. For extremely thin films (<3 nm), techniques with high surface sensitivity such as Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy (XPS) are commonly employed. Sampling depth depends on the attenuation length of the emitted photoelectrons or Auger electrons.Electron spectroscopy techniques are also used to characterize thicker films by adding a microsectioning method to the experiment, most commonly ion sputtering.

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