bluuebunny/crossref_metadata_2025_split huggingface dataset:
Molecules on Semiconductors: From Chromogenic Interactions to Information Processing Devices
Authors: Szacilowski Konrad , Kwolek Przemyslaw , Mech Justyna , Pilarczyk Kacper , Oszajca Marek 
Published: February 2020

Rapid development of electronic technologies requires new semiconducting and dielectric materials of superior quality. Recently new applications (like LCD and OLED displays) initiated the employment of various organic materials (pentacene, oligothiophenes) as semiconductors for thin layer field effect transistors. Micro- and nanoelectronics also search for new materials of unusual properties. One of the recent examples is a memristor - a memory resistor. This fourth fundamental passive element (like resistor, capacitor and inductor) was predicted theoretically in early seventies and demonstrated experimentally 37 years later. Memristors have opened new fields of electronics and enabled fabrication of circuits with synaptic properties and learning abilities. Not surprisingly the prototype of this amazing device was based on very popular wide band gap semiconductor: titanium dioxide. This material is widely used as photocatalyst and in dye-sensitized solar cells, but its applications in electronic elements are relatively rare. However, TiO2 is the first material for which the photoelectrochemical photocurrent switching effect was described, which further resulted in new materials for unconventional logic devices. Other metal oxides, especially binary ones (e.g. PbMoO4, BiVO4) exhibit similar semiconducting properties (the same n-type conductivity, similar band gap values), but their properties as active materials in micro/nanoelectronic devices are almost not recognized. The role of these oxide semiconductors may be two-fold. Firstly, they can provide a solid substrate and a scaffold for self-assembly of molecular layers. Transition metal oxides should provide self-assembly template for organic molecules. Secondly, due to their non-innocent interactions with organic ligands may substantially modify properties of organic materials. These interactions may be strong enough to generate new (emergent) optical and electronic features which are not present in parent compounds. Photoinduced electron transfer (PET), optical electron transfer (OET) and photoelectrochemical photocurrent switching effect (PEPS) are such phenomena.
This contribution presents the nature of chromogenic interactions from the quantum-chemical point of view on the example of aromatic hydrocarbons anchored to various d
0 ions in the coordination environment present in semiconducting oxide phases. The consequences of these interactions are related to the functional properties which are shown from experimental perspective in the second part. Optoelectronic switches, logic gates, binary computing circuits and artificial synaptic devices will be discussed in detail.
Simple Strategies Towards Lowering the Activation Potential of Electrochromic Devices. Case Study on TiO2-Viologen Based Displays
Authors: Manceriu Laura , Danine Abdelaadim , Da Rocha Mathias , Rougier Aline 
Published: February 2020

The purpose of this study is to demonstrate the easy tuning of the activation potential of electrochromic devices (ECDs) by varying the nature of the electrolyte and counter electrode. For this purpose ECDs with a simplified configuration were fabricated (i) by using TiO2-viologen deposited on Transparent Conducting Oxide (TCO) as electrochromic active layer (EC1) and (ii) by replacing the counter electrode consisting of an electrochromic material and a conductive one (EC2/TCO) in a traditional 5-layers battery type ECD (TCO/EC1/electrolyte/EC2/TCO) by a metal electrode.
Firstly a comparison is made between polymer membrane and aqueous gel electrolytes with varying compositions, focusing on the influence of ionic conductivity on the contrast and the switching time. Low toxicity aqueous based gel electrolytes were prepared from gelatin, glycerol, and NaCl/LiCl as ion precursor, whereas the polymer membrane electrolyte consisted of 0.3M LiTFSI in BMITFSI with 40% PMMA. At the end of our study we have investigated the influence of the metal counter electrode nature, more precisely the type of metal and its surface morphology, on the devices response time and optical modulation.
The use of an aqueous gel electrolyte (~10-3/-2 S/cm) instead of a membrane electrolyte (~10-4/5 S/cm) leads to lowering the working potential window; ECDs are colored at -0.5V and bleached at 0V (Fig. 1), turning from blue to white in few seconds. Also, higher contrast (DR) and shorter coloration (tc) and bleaching (tb) times are reached for electrolytes exhibiting higher ionic conductivity (σ). The morphology of the metal electrode influences mainly the coloration kinetics, and the difference is more obvious for the electrolytes with lower ionic conductivity (Fig. 1).

Figure 1
Fibroin Films Doped with Lithium Ions for Application in Electrochromic Devices
Authors: Silva M. M. , Pereira Rui F. P. , de Zea Bermudez V. 
Published: February 2020

Silk fibroin is a commonly available natural biopolymer produced in specialized glands of arthropods, with a long history of use in textile production and also in health cares. The exceptional intrinsic properties of these fibers, such as self-assembly, machinability, biocompatibility, biodegradation or non-toxicity, offer a wide range of exciting opportunities [1].
Silk research is mainly devoted regarding the biomaterials field. Although, it has long been recognized that silk is can be a rich source of inspiration for designing new materials with tailored properties, enhanced performance and high added value for targeted applications, opening exciting new prospects in the domain of materials science and related technological fields, including bio-friendly integration, miniaturization and multifunctionalization. Progresses in new technological fields such as optics, photonics and electronics are emerging [2,3]. The incorporation of polymer electrolytes as components of various devices (advanced batteries, smart windows, displays and super-capacitors) offers significant advantages relative to traditional electrolytes, including enhanced reliability and improved safety.
Preliminary tests performed with a prototype electrochromic device (ECD) incorporating the most promising electrolyte composition, silk fibroin films doped with lithium ions (LiTFSI and LiBF4) as electrolyte and WO3as cathodic electrochromic layer, are extremely encouraging.

Acknowledgements:

This work was supported by Fundação para a Ciência e a Tecnologia (FCT) and Feder (contracts PTDC/CTM-BPC/112774/2009, PEst-OE/QUI/UI0616/2014 and PEst-C/QUI/UI0686/2013) and COST Action MP1202 “Rational design of hybrid organic-inorganic interfaces”. R.F.P.P. acknowledges FCT and program POPH/FSE for a grant (SFRH/BPD/87759/2012). COST Action MP1202 “Rational design of hybrid organic-inorganic interfaces”.M. M. Silva acknowledges CNPq, for the mobility grant provided by this institution.

References

[1] L. B. Shi et al.Biomaterials, 2014, 35, 1519-1530
[2] R. F. P. Pereira, M. M. Silva, V. de Zea Bermudez, Macromol.
Mater.
Eng.2014, 299, DOI: 10.1002/mame.201400276
[3] H. Tao, D. L. Kaplan and F. G. Omenetto, Adv. Mater., 2012, 24, 2824-2837
Color e-Paper Technology with Electrochemistry
Authors: Kobayashi Norihisa 
Published: February 2020

The demand for global environmental conservation and decrease of CO2 evolution require the development of “new imaging media”, instead of paper. This is called “electronic paper (e-Paper)”. Electrochromism (EC) is defined as a reversible color change by electrochemical reaction and has several features such as color variation, memory property and so on. Electrochromic display (ECD) is therefore a potential candidate to realize full color e-Paper. EC materials showing color changes from clear to the three primary colors such as RGB or CMY should be required to realize full color e-Paper.
This paper focuses on novel e-paper technology with electrochemical reaction. First, we will show our recent results on EC materials and devices which show three primary colors (CMY) in subtractive color mixture system1, 2. Electrodeposition is also attractive method to create colors3-5. We will discuss the mechanism of electro-deposition and a wide range of its applications.
We also demonstrated novel display device with dual reflective and emissive modes. This is called dual mode display (DMD). DMD enables both reflective and emissive mode of representation which can be chosen as a situation demand. We fabricated DMD by combining both electrochromic (EC) and electrochemiluminescence (ECL) materials in a single cell6, 7. The device functions as an EC cell in the reflective mode, and as an ECL cell in the emissive mode.
References; 1)
Solar Energy Materials and Solar Cells, 92 136 (2008), 2)
Solar Energy Materials and Solar Cells, 104, 140 (2012), 3)
Adv. Mater., 24, OP122 (2012), 4)
Adv. Mater., 25, 3197 (2013), 5)
Chem. Mater, 26, in press (2014). 6)
Chem. Lett., 39, 1309 (2010), 7)
Phys. Chem. Chem. Phys., 13, 19420 (2011).
An All-in-One Electrochromic Device Containing Thermally Cured Dual Functional Viologen
Authors: Kao Sheng-Yuan , Lu Hsin-Che , Chang Ting-Hsiang , Kung Chung-Wei , Ho Kuo-Chuan 
Published: February 2020

Viologens are promising electrochromic material due to their high optical contrast when switched between its oxidized/reduced states.1,2 However, the utilization of the viologen in liquid form would lead to leakage problems.3Herein, a thermal-cured electrochromic gel was prepared through the utilization of dual functional vinyl-bearing viologen, which acts as an electrochromic chromophore and at the same time serves as a thermal cross-linker. When this dual functional viologen was injected into an electrochromic device (ECD), followed by the thermal treatment, an uniform electrochromic gel can be obtained. This approach provides an easier fabrication of the all-in-one leakage-free ECD. Moreover, this leakage-free ECD exhibits good compatibility with electrolytes and other chromophores, thus resulting in uniform color change. Significant optical contrast can be achieved in this ECD (as shown in Fig. 1(a)). Ultimately, This ECD reveals reversible coloring and bleaching processes while maintaining high transmittance change (> 55%) at 615 and 570 nm (as shown in Fig 1(b) and Fig. 1(c)).
REFERENCES
(1) Mortimer, R. J. Chem. Soc. Rev.1997, 26, 147.
(2) Mortimer, R. J.; Varley, T. S. Chem. Mat.2011, 23, 4077.
(3) Thakur, V. K.; Ding, G. Q.; Ma, J.; Lee, P. S.; Lu, X. H. Adv. Mater. 2012, 24, 4071.

Figure 1
Spatially Resolved Spectro-Electrochemistry Using Soft X-Ray Scanning Transmission X-Ray Microscopy
Authors: Hitchcock Adam P , Rosendahl Scott M. , Appathurai Narayan 
Published: February 2020

We are using soft X-ray scanning transmission X-ray microscopy (STXM) [1] at CLS beamline 10ID1 (SM) and at ALS beamline 5.3.2.2 to investigate Cu deposition onto, and stripping from a Au surface. Electrochemical reduction of Cu(II) under acid conditions is a commonly used process to deposit copper for integrated circuit interconnects. The reduction of Cu(II) to Cu(0) proceeds via a Cu(I) intermediate, which can be detected under neutral or basic conditions. Cu 2p and O 1s spectromicroscopy is used to analyze initial and final states, follow the process in situ, and search for intermediate species. The apparatus and techniques for spectro-electrochemical-microscopy will be described. Ex situ and in situ deposition & stripping of copper from CuCl2(aq) and CuSO4(aq) electrolytic solutions will be described. Progress towards an in situ flow electrochemical cell and a faster response time for kinetics measurements will be presented.
STXM performed on BL 10ID1 at CLS and on BL 5.3.2.2 at ALS. Research supported by NSERC and the Catalyst Research for Polymer Electrolyte Fuel Cells (CaRPE-FC) network.
[1] A.P. Hitchcock, Soft X-ray Imaging and Spectromicroscopy in Handbook on Nanoscopy, eds. G. Van Tendeloo, D. Van Dyck and S. J. Pennycook 2012. (Wiley)

Figure 1
(Invited) High-Performance and Long-Lifetime Oxygen Evolution Catalysts for Proton Exchange Membrane Water Electrolysis
Authors: Rasimick Brian , Alia Shaun M , Pivovar Bryan S , Xu Hui 
Published: February 2020

Hydrogen production from proton exchange Hydrogen production from proton exchange membrane (PEM) water electrolysis is attractive due to its simple and clean nature. However, the technology is still expensive due to high materials cost for the catalysts, membrane, and bipolar plate. In most commercial processes, iridium (Ir) black is used as an oxygen evolution reaction (OER) catalyst at the anode. A high precious group metal (PGM) loading (> 4mg/cm2) has been used due to significant anode activation loss caused by sluggish kinetics of the OER.
Instead of using commercial Ir black, we have developed two types of high-performance OER catalysts for PEM water electrolysis. One is Ir dispersed on some supports with high oxidation resistance; the other is extended continuous nanostructures including Ir nanowires and Ir nanotubes (see Figure 1).
First, Ir nanoparticles have been dispersed on tungsten-doped titanium oxide (Ir/W-TiO2). Doping of TiO2 with an element W can substantially enhance the electronic conductivity of TiO2 while maintaining its high corrosion resistance at high electrolyzer operating voltages. A series of Ir/ W-TiO2 catalysts with decreasing Ir loading from 70 wt. % to 25 wt. % has been synthesized. TEM images illustrates that Ir nanoparticles vary from 1 nm to 5 nm. The electrochemical surface area (ECSA) has been measured via mercury underpotential deposition (UPD).
In addition to Ir/W-TiO2, Ir nanotubes have been synthesized via a porous alumina template. The template was coated with an iridium precursor by subliming iridium precursor at an appropriate temperature. The template support was removed via chemical etchings. The average length of the Ir nanotubes is 5mm and the diameter ranges from 250 – 400 nm with a wall thickness of ≤50 nm. The template pore size and process conditions are being varied to change the dimension of the Ir nanotubes.
The activity and durability of these catalysts have been evaluated in rotating disk electrodes (RDEs) and electrolyzers. Selected catalysts have reduced PGM loading of electrodes by a factor of 10 while maintaining equivalent electrolyzer performance. These catalysts will help to lower the PEM electrolyzer capital cost making PEM water electrolysis more viable for a variety of applications.

Figure 1
New Catalysts for the Hydrogen and Oxygen Evolution Reactions
Authors: Gross Zeev , Mahammed Atif 
Published: February 2020

We have recently introduced corrole metal complexes (metallocorroles) as catalysts for various reactions, including those that are of prime importance for water splitting into its elements- the hydrogen and oxygen evolution reactions. A careful choice of substituents on the corrole ligand and the kind of metal ion chelated by them allows for lowering of the electrocatalytic overpotential and increasing reactivity.
An arsenal of electrochemical and spectroscopic methodologies, which in the case of metallocorroles is very rich, was applied for acquiring highly valuable information about the mechanisms of action (see upper part of the Figure for the hydrogen evolution reaction). Preliminary results regarding water oxidation with the aid of immobilized catalysts (see lower part of the Figure) will be presented as well.
REFERENCES
“Cobalt Corrole Catalyst for Efficient Hydrogen Evolution Reaction from H2O under Ambient Conditions: Reactivity, Spectroscopy and DFT Calculations”, Inorg. Chem.
2013, 52, 3381-3387.
"The Cobalt Corrole Catalyzed Hydrogen Evolution Reaction: Surprising Electronic Effects and Characterization of Key Reaction Intermediates" Chem. Commun.
2014, 50, 2725-2727.

Figure 1
Electronic Properties of III-V Semiconductor Photocathode-Water Interfaces: Predictions from First-Principles Calculations
Authors: Pham Tuan Anh , Wood Brandon C. , Ogitsu Tadashi 
Published: February 2020

Photoelectrochemical (PEC) cells based on III-V semiconductor photocathodes offer a promising avenue for hydrogen production from water and sunlight. The efficiency of these devices depends on the electronic structure of the interface between the photocathode and liquid water, including the alignment between the semiconductor band edges and the water redox potential. Accurate theoretical predictions of this quantity remain a challenging task, as conventional electronic structure methods such as density functional theory (DFT) often yield substantial errors [1]. In this talk, we present calculations of the electronic properties of two representative III-V semiconductor electrodes, i.e. GaP and InP, at the interface with water using a combination of first-principles molecular dynamics simulations and many-body perturbation theory (MBPT). We show that the use of MBPT is key to obtain band alignments in agreement with experimental measurements. In addition, we describe the relationship between interfacial structure, electronic properties of semiconductors and their reactivity in aqueous solutions.
1. T. A. Pham, D. Lee, E. Schwegler and G. Galli, J. Am. Chem. Soc. in press (2014).
This work was supported by the U.S. Department of Energy at the Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.
Photoelectrochemical Reduction of Carbon Dioxide to Methanol at Hybrid System Composed of Titanium(IV) and Copper(I) Oxides
Authors: Szaniawska Ewelina , Bienkowski Krzysztof , Solarska Renata , Rutkowska Iwona Agnieszka , Kulesza Pawel J 
Published: February 2020

Due to gradual decline of energy resources, there has been growing interest in new energy systems that include direct transformation of solar energy to chemical energy using oxide semiconductor materials. Furthermore, carbon dioxide (CO2), as the primary greenhouse gas also emitted through human activities, could be converted using sunlight to organic compounds. The approach permits simultaneous generation of alternative fuels and environmental remediation of carbon emissions from the continued use of conventional fuels.
The aim of this work has been to develop hybrid materials by utilizing combination of metal oxide semiconductors thus capable of effective photoelectrochemical reduction of carbon dioxide. The combination of titanium (IV) oxide (TiO2) and copper (I) oxide (Cu2O) has been explored toward the reduction of carbon (IV) oxide (CO2) before and after sunlight illumination. Application of the hybrid system composed of both above-mentioned oxides resulted in high current densities originating from photoelectrochemical reduction of carbon dioxide mostly to methanol (CH3OH) as demonstrated upon identification of final products.
In particular, fabrication of the hybrid system (heterojunction photocathode) of TiO2 and Cu2O (on the conducting glass) has required first the cathodic electrodeposition copper (I) oxide. The latter step has been followed by sputtering n-type titanium (IV) oxide. The spectral responses of the Cu2O/TiO2­ electrode is comparable to that of simple Cu2O, and the photoresponse is enhanced at relatively short wavelengths. It is reasonable to expect that the light absorbed by the inner Cu2O film produces energetic electron (e-) – hole (h+) pairs. The excited electrons are driven through the conduction band to the external TiO2/electrolyte interface. The role of TiO2 is not stabilizing; the oxide is also expected to prevent the recombination of charge carriers (e- - h+ pairs). By using gas chromatography with the flame ionization detector, it was confirmed that methanol predominates as a final product.
Interfacial Structure of Nafion
Authors: Dura Joseph A. , DeCaluwe Steven C , Kienzle Paul 
Published: February 2020

While ion-conducting materials are primarily considered for their use as electrolytes (which depend upon their bulk properties, i.e. conductivity, crossover rejection, and material strength) their interfacial properties are becoming increasingly relevant for optimizing electrochemical devices. Ionomers are often applied as binders, which coat fuel cell catalyst electrode particles with layers that are several nanometers thick. Here confinement effects or the interfacial properties of the ionomer may directly influence the efficiency of the electrochemical device. Furthermore various fillers are increasingly used to modify the properties of ionomers to improve the bulk electrolyte characteristics. For example silica particles are added to Nafion to increase water retention especially at high temperatures in fuel cells and to reduce V crossover in flow batteries.
Neutron reflectometry, NR, is capable of determining structure with sub-Angstrom precision in idealized planar interfaces. Because of isotopic contrast variations it is particularly sensitive to certain elements such as H (and thus water) as well as Li, V, and numerous others. Herein, NR has been applied to investigate finite-size effects on the lamellar ordering of water domains in Nafion at interfaces with hydrophilic materials. Moreover, contrast variation was employed to quantify the segregation of the sulfonate groups from the fluorocarbon chains in Nafion.
These results confirm the lamellar structure previously observed on hydrophilic substrates, and demonstrate that for hydrated films they can accurately be described as layers rich in both water and sulfonate groups, alternating with water-poor layers containing an excess of the fluorocarbon backbone. The thickness of these layers increases slightly and the amplitude of the oscillation that defines the water volume fraction exponentially decreases away from the hydrophilic interface. A partial monolayer of sulfonate groups is determined to be bonded to the SiO2, accompanied by a large excess of water (compared to that expected by the water-to-sulfonate ratio, λ, of the remainder of the film). Ultrathin (6nm) Nafion coatings that were limited in extent enough to truncate this lamellar region showed a depth profile nearly identical to thicker films, indicating that there are no confinement or surface effects altering the structure. For films dehydrated for 2 hours at 60 °C, the composition oscillations are decreased in amplitude and extent from the interface. Comparing the SLD profile measured for dried films to modeled composition profiles derived by removing water from the hydrated lamellae suggests incomplete remixing of the polymer groups upon dehydration, indicated either limited polymer mobility or retained equilibrium structures at in the Nafion/SiO2 interface.
Toward a Single-Ion Nanocomposite Electrolyte for Lithium Batteries
Authors: Zhao Hui , Baker Gregory , Liu Gao 
Published: February 2020

Lithium ion battery has been widely used nowadays. Occurrence of polarization has been a problem in the currently used electrolyte, especially in high-current application such as hybrid vehicles. In this work we modified silica nanoparticles with polyelectrolytes containing anion groups, lithium cation is the counterion. To get the lithium conductor, the polymer modified nanoparticles were blended with poly(ethylene oxide) oligomer. Movement of the anions were largely restricted by surface anchored polymer backbones, lithium ion became the only ion that is conducting current. Four different polymer structures were explored in this study, aiming at improving conductivity of the material. FTIR and TGA were used to prove successful synthesis of the polymer modified particles. AC impedance was used to measure the conductivity with a room temperature conductivity above 10-5 S/cm. This composite electrolyte has the potential to suppress lithium dendrite growth and enable the use of lithium metal anode in rechargeable batteries.