Conductive Glass Research Articles

Hafnium Oxide Nanostructured Thin Films: Electrophoretic Deposition Process and DUV Photolithography Patterning.

In the frame of the nanoarchitectonic concept, the objective of this study was to develop simple and easy methods to ensure the preparation of polymorphic HfO2 thin film materials (<200 nm) having the best balance of patterning potential, reproducibility and stability to be used in optical, sensing or electronic fields. The nanostructured HfO2 thin films with micropatterns or continuous morphologies were synthesized by two different methods, i.e., the micropatterning of sol-gel solutions by deep ultraviolet (DUV) photolithography or the electrophoretic deposition (EPD) of HfO2 nanoparticles (HfO2-NPs). Amorphous and monoclinic HfO2 micropatterned nanostructured thin films (HfO2-DUV) were prepared by using a sol-gel solution precursor (HfO2-SG) and spin-coating process following by DUV photolithography, whereas continuous and dense monoclinic HfO2 nanostructured thin films (HfO2-EPD) were prepared by the direct EPD of HfO2-NPs. The HfO2-NPs were prepared by a hydrothermal route and studied through the changing aging temperature, pH and reaction time parameters to produce nanocrystalline particles. Subsequently, based on the colloidal stability study, suspensions of the monoclinic HfO2-NPs with morphologies near spherical, spindle- and rice-like shapes were used to prepare HfO2-EPD thin films on conductive indium-tin oxide-coated glass substrates. Morphology, composition and crystallinity of the HfO2-NPs and thin films were investigated by powder and grazing incidence X-ray diffraction, scanning electron microscopy, transmission electron microscopy and UV-visible spectrophotometry. The EPD and DUV photolithography performances were explored and, in this study, it was clearly demonstrated that these two complementary methods are suitable, simple and effective processes to prepare controllable and tunable HfO2 nanostructures as with homogeneous, dense or micropatterned structures.

(Digital Presentation) Electrical Properties of Nanocarbon-Polyaniline Nanocomposites

Macroscopic objects such as fibers and films formed from a combination of nanocarbon materials and polymers have promising electrical [1], thermal [2], thermoelectric [3], and mechanical [4] properties. In particular, composites of nanocarbon and conductive polymers revealed that they can constitute key parts of batteries [1] and thermoelectric generators [3]. In literature, it is possible to find many synthesis methods of this type of material. One of the most common approaches is electrochemical, wherein monomers are polymerized onto the nanocarbon surface due to its highly conducting nature [5]. Polyaniline (PANI) is the oldest and still one of the most popular conductive polymers used in this area. That is because PANI is relatively simple to manufacture at low cost and effort. Moreover, it has good mechanical strength and tunable electrical conductivity, which depend on the kind of PANI. This polymer has three forms: pernigraniline – fully oxidized (purpure/red), emeraldine – partially oxidized (blue/violet), and leucoemeraldine – fully reduced (black) [6]. Emeraldine achieves the highest conductivity when doped with Brøstead acids such as HCl, H2SO4, HBF4 [7].The goal of this study was to exploit the phenomenon of the hydrophilic surface of carbon nanostructure caused by thermal annealing, described by us previously [8], to electropolymerize aniline onto free-standing films from nanocarbon. The films were manufactured by the wet method [8] using single-walled nanotubes (SWCNTs) exclusively and SWCNTs/graphene nanoplatelet composite. Electropolymerization was used to synthesize PANI on the surface of these materials. To establish the parameters of synthesis of different forms of PANI, voltage ranges between [(-1.6 V) – (1.6 V)] were investigated. The films were tested as a counter and a working electrode in this process. After the synthesis, the composites were investigated by optical and Scanning Electron Microscopy, Raman spectroscopy, Atomic Force Microscopy. Moreover, water contact angles, electrical conductivity values, and Seebeck coefficients were determined. Composites containing all three PANI forms have been synthesized and thoroughly analyzed to elucidate the structure-property relations. Consequently, correlations between the forms of PANI and the characteristics of nanocomposites were established. Depending on the amount and type of PANI on the surface, the character of the nanocarbon films was affected considerably. For example, coating of the material with emeraldine salts enhanced the electrical conductivity of the films by about 60% [9], while simultaneously making the material much stronger.[1] L. Xiao, Y.H. Sehlleier, S. Dobrowolny, F. Mahlendorf, A. Heinzel, C. Schulz, H. Wiggers, Novel Si-CNT/polyaniline nanocomposites as Lithium-ion battery anodes for improved cycling performance, Mater. Today Proc. 4 (2017) S263–S268. doi:10.1016/J.MATPR.2017.09.197.[2] Z. Duan, Y. Luo, Z. Luo, W. Yu, C. Liu, S. Fan, The influence of charging and discharging on the thermal properties of a carbon nanotube/polyaniline nanocomposite electrode, RSC Adv. 9 (2019) 7629–7634. doi:10.1039/C9RA00151D.[3] R. Wu, H. Yuan, C. Liu, J. Le Lan, X. Yang, Y.H. Lin, Flexible PANI/SWCNT thermoelectric films with ultrahigh electrical conductivity, RSC Adv. 8 (2018) 26011–26019. doi:10.1039/c8ra04863k.[4] M.R. Saeb, P. Zarrintaj, Polyaniline/graphene-based nanocomposites, Fundam. Emerg. Appl. Polyaniline. (2019) 165–175. doi:10.1016/B978-0-12-817915-4.00010-5.[5] C. Oueiny, S. Berlioz, F.X. Perrin, Carbon nanotube–polyaniline composites, Prog. Polym. Sci. 39 (2014) 707–748. doi:10.1016/J.PROGPOLYMSCI.2013.08.009.[6] S.C. Rasmussen, The Early History of Polyaniline: Discovery and Origins, An Int. J. Hist. Chem. Subst. 1 (2017) 99–109. doi:10.13128/substantia-30.[7] Q. Qin, Y. Guo, Preparation and characterization of nano-polyaniline film on ITO conductive glass by electrochemical polymerization, J. Nanomater. 2012 (2012). doi:10.1155/2012/519674.[8] D. Janas, G. Stando, Unexpectedly strong hydrophilic character of free-standing thin films from carbon nanotubes, Sci. Rep. 7 (2017) 12274. doi:10.1038/s41598-017-12443-y.[9] G.Stando, P. Stando, P. Chulkin, M. Salhman, M. Lundström, D. Janas, Electropolymerization of aniline onto hydrophilic nanocarbon films (in preparation)G.S. and P.S. would like to thank the Ministry of Science and Higher Education of Poland for financial support of research (under Diamond Grant, grant agreement 0036/DIA/201948). G.S. also would like to thank European Union for thanks for financing the costs of the conference (European Social Fund, grant nr POWR.03.05.00-00-Z305) and National Agency for Academic Exchange of Poland (under the Iwanowska program, grant agreement PPN/IWA/2019/1/00017/UO/00001) for financial support during the stay at the University of Pittsburgh in the USA. G.S. and H.L. acknowledge NSF (CBET-2028826) for partial support of this work. P. S. acknowledges the National Agency for Academic Exchange of Poland (under the Academic International Partnerships program, grant agreement PPI/APM/2018/1/00004) for supporting training in the Aalto University. G.S, P.S and D.J. would like to thank the National Centre for Research and Development, Poland (under the Leader program, grant agreement LIDER/0001/L-8/16/NCBR/2017).

Highly Ordered Supramolecular Assembled Networks Tailored by Bioinspired H-Bonding Confinement for Recyclable Ion-Transport Materials

Highly Ordered Supramolecular Assembled Networks Tailored by Bioinspired H-Bonding Confinement for Recyclable Ion-Transport Materials

DC sputter deposited TiO2 layers on FTO: towards a maximum photoelectrochemical response of photoanodes

In this work, we examine the photoelectrochemical response of TiO2 layers prepared by reactive DC sputter deposition on conductive glass (FTO). We show that adequate conditioning of the FTO by a very thin (few nm thick) Ti interlayer and optimizing the sputter parameters, compact TiO2 anatase layers can be produced that reach incident photocurrent conversion efficiencies (IPCE) maxima peaking at 75%. This is outperforming many of the best titania photoanode structures (including high surface area 1D and 3D titania structures). The key role of the interlayer is to promote the crystallization of titania in the anatase form during the annealing process (as opposed to rutile in the interlayer-free case). Without this interlayer, an IPCE maxima of ≈43% is obtained for otherwise identically processed electrodes. The present work thus describes a most simple straightforward approach for fabricating compact, high-efficiency TiO2 (anatase) photoanodes.Graphical abstract

Colloidal lithography as a novel approach for the development of Ni-nanocavity insulin sensor

In this study, a highly sensitive, fast, and selective enzyme-free electrochemical sensor based on the deposition of Ni cavities on conductive glass was proposed for insulin detection. Considering the growing prevalence of diabetes mellitus, an electrochemical sensor for the determination of insulin was proposed for the effective diagnosis of the disease. Colloidal lithography enabled deposition of nanostructured layer (substrate) with homogeneous distribution of Ni cavities on the electrode surface with a large active surface area. The morphology and structure of conductive indium tin oxide glass modified with Ni cavities (Ni-c-ITO) were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The diameter of the resulting cavities was approximately 500 nm, while their depth was calculated at 190 ± 4 nm and 188 ± 18 nm using AFM and SEM, respectively. The insulin assay performance was evaluated by cyclic voltammetry. Ni-c-ITO exhibited excellent analytical characteristics, including high sensitivity (1.032 µA µmol−1 dm3), a low detection limit (156 µmol dm−3), and a wide dynamic range (500 nmol dm−3 to 10 µmol dm−3). Finally, the determination of insulin in buffer with interferents and in real blood serum samples revealed high specificity and demonstrated the practical potential of the method.

Preparation of high-efficiency anti-reflective oxide electrodes and their application in biomedical testing and thin-film lithium batteries

Nanomaterials hold great potential in the development of lithium-ion microbatteries and could assist in developing ever smaller and more reliable power sources to facilitate 21st Century life. Professor Kuan-Jiuh Lin is based in the Department of Chemistry, National Chung Hsing University, Taiwan, and runs the Interfacial Optical-Electronic (IOE) Lab. He and his team leader Dr Wen-Yin Ko are working to address gaps in nanotechnology, including how to conquer the strong interfacial coupling between the porous semiconductor membrane and the electro-plasmon metal-surface film. Their research is expected to have broad applications across electronics and optoelectronics. In a recent project, the researchers are working to develop more efficient lithium-ion microbatteries (micro-LIBs) using active nanostructured anode materials such as carbon nanomaterials composed of porous carbon, graphene and carbon nanotubes (CNTs). The researchers have developed a lightweight and high-rate CNT-based anode system that holds great potential for fast-charging batteries. The team has also created metal-doped MnO2 nanowalls with inter-networked vertically-oriented three-dimensional (3D) porous frameworks directly onto a AgCNT modified current collector, resulting in a superior performance anode material for LIBs. The researchers also created a novel 3D porous scaffold anode material of silicon–porphyrin pearl-chain-like nanowires which was placed onto the surface of a bundled titanium dioxide (TiO2) nanowire. In a world first, Lin and the team were able to achieve dial functionalities of antireflective and electrochemical properties-based anatase TiO2 nanowire devices with a high-porosity cross-linked geometry directly grown onto transparent conductive glass.

Tailoring oxygen evolution performances of carbon nitride systems fabricated by electrophoresis through Ag and Au plasma functionalization

The strategic interest in the production of green hydrogen by sunlight-activated water splitting has stimulated significant efforts aimed at the implementation of active and cost-effective catalysts for the oxygen evolution reaction (OER), the overall process bottleneck. Herein, we report on an original fabrication route to OER electrocatalysts based on graphitic carbon nitride. In particular, the target systems were deposited on conductive glass substrates via a simple electrophoretic technique and functionalized with highly dispersed noble metals (Au, Ag or Au + Ag) in low amounts by radio frequency (RF)-sputtering under mild conditions. An advanced material characterization revealed the possibility of tailoring carbon nitride morphology as a function of the used precursor and of achieving a homogeneous spatial distribution of the functionalizing metals. The latter ranged from atomically dispersed (silver), to low-sized nanoaggregates (gold) or partially alloyed core–shell nanoparticles (gold+silver), with an intimate metal-nitride interfacial contact. Functional tests evidenced a remarkable sensitivity to Vis light even at low applied potentials, and photoelectrocatalytic performances directly dependent on the nature of metal species and on the features of the underlying carbon nitride deposit. These evidences, rationalized mainly on the basis of Schottky junctions and the possible concurrence of surface plasmon resonance (SPR), candidate the proposed strategy as a versatile route to cheap and efficient OER electrocatalysts for energy conversion.

Investigation of lithiation/delithiation processes in ceramic solid electrolyte by means of Neutron Depth Profiling

Rechargeable all-solid-state Li batteries with solid electrolytes (SE) are a prospective solution for safe and high-capacity energy storage systems. In recent decades, several types of SE with high ionic conductivity have been developed and tested with different techniques. In this study, we employed a non-destructive nuclear analytical method, Neutron Depth Profiling (NDP), to investigate the response of one of the promising electrolytes, Lithium Conductive Glass Ceramic (LICGC), to the applied voltage +2.8 V. The in-situ NDP measurements made it possible to directly monitor the migration of lithium ions in the electrolyte and to observe and quantify the formation of a space charge layer with depleted Li atoms, which depends on the biasing time.

Multi-field driven thermochromic films and preparation of multi-color patterns

ABSTRACT In this paper, multi-field driven thermochromic films (TCF) were successfully prepared firstly. The upper layer is polymer-dispersed liquid crystal (PDLC) film prepared by polymerisation-induced phase separation (PIPS), and the lower layer is thermochromic liquid crystal microcapsule film prepared by centrifugal spin-coating method. The effects of diluent content, liquid crystal content and spin coating speed on the electro-optical properties and morphology of the thermochromic films were investigated by three sets of experiments secondly. Finally, multi-field driven multi-colour patterns were successfully prepared by film formation on conductive glass and flexible conductive films. Thermal ageing tests proved that the thermochromic films possess better service life, which provides a possibility for the wide application of liquid crystal films.

One-step preparation of SnO2-AuNPs as nanocomposites on photoelectrodes to enhance photoelectrochemical detection of nitrite and superoxide

The integration of plasmonic metal nanoparticles and semiconductors improves the photoelectric conversion efficiency. We describe here a simple method for preparing photoelectrodes modified with nanocomposites of tin oxide (SnO2) and gold nanoparticles (AuNPs). This preparation process is more convenient, economical, and efficient than the previous methods. The nanocomposite of SnO2-AuNPs on indium tin oxide (ITO) conductive glass electrodes enhanced photoelectric conversion and increased conductivity. The electrodes prepared with SnO2-AuNPs nanocomposites were used as photoanodes in photoelectrochemical methods for the determination of nitrite (NO2−) and superoxide radical (O2−). The detection of superoxide radicals was achieved by stoichiometric conversion of superoxide radicals to nitrite, which overcomes a common problem of chemical instability of superoxide radicals. The photoelectrochemical method for the determination of NO2− had a detection limit of 0.1 nmol/L and a linear dynamic range from 10−9 to 10−5 mol/L. The method was successfully used to assess the photochemical generation of O2− by irradiating a photosensitizer, rose bengal (RB). The photoelectrochemical responses increased with the concentration of the photosensitizer and the time of photo irradiation (532 nm) as expected.

Study on the optical properties of FTO/W-V2O5/FTO composite film under electric induced phase transition

W-doped V2O5 thin film was prepared by sol-gel method and post annealing process on fluorine-doped SnO2(FTO) conductive glass substrate. The FTO/W-V2O5/FTO sandwiched structure was fabricated on FTO substrate using photolithography and a chemical etching process. The crystallinity, surface morphology and photoelectric properties of the composite films were tested under different temperatures and applied voltages. The transmittance difference of FTO/W-V2O5/FTO composite film at the wavelength of 750 nm is 11.24% from 23 °C to 300 °C without voltage applied. Under the applied voltage of 5V, the transmittance difference can reach 13.50% from 23 °C to 300 °C. After repeated application of voltage and heating, the structure still maintains stable performance and has good electrical and thermal control capabilities. It is expected to be applied in new optoelectronic devices.

Visible Light Reductive Photocatalysis of Azo-Dyes with n-n Junctions Based on Chemically Deposited CdS.

New composite photocatalysts have been obtained by chemical bath deposition of CdS on top of either nanostructured crystalline ZrO2 or TiO2 films previously deposited on conductive glass FTO. Their morphological, photoelectrochemical and photochemical properties have been investigated and compared. Time resolved spectroscopic, techniques show that in FTO/TiO2/CdS films the radiative recombination of charges, separated by visible illumination of CdS, is faster than in FTO/ZrO2/CdS, evidencing that carrier dynamics in the two systems is different. Photoelectrochemical investigation evidence a suppression of electron collection in ZrO2/CdS network, whereas electron injection from CdS to TiO2 is very efficient since trap states of TiO2 act as a reservoir for long lived electrons storage. This ability of FTO/TiO2/CdS films is used in the reductive cleavage of N=N bonds of some azo-dyes by visible light irradiation, with formation and accumulation of reduced aminic intermediates, identified by ESI-MS analysis. Needed protons are provided by sodium formate, a good hole scavenger that leaves no residue upon oxidation. FTO/TiO2/CdS has an approximately 100 meV driving force larger than FTO/ZrO2/CdS under illumination for azo-dye reduction and it is always about 10% more active than the seconds. The films showed very high stability and recyclability, ease of handling and recovering.

SnS Nanoparticles and MoS2 Nanosheets Co-Decorated TiO2 Nanorod Film with Remarkable Photocatalytic and Photoelectrochemical Properties

TiO2/SnS/MoS2 ternary nanorod arrays were synthesized on a fluorine-doped tin oxide (FTO) conductive glass by a successive hydrothermal method. The morphology, microstructure, optical properties, photodegradation activity, photoelectrochemical performance, and charge transport mechanism of TiO2/SnS/MoS2 were systematically studied. It was found that SnS and MoS2 with a narrow bandgap can facilitate light absorbance of TiO2/SnS/MoS2 heterostructures across the visible range, improving the utilization of sunlight. TiO2/SnS/MoS2 exhibits the maximum photodegradation rate (61.54%) for Rhodamine B (RhB) in 60 min with a pseudo-first-order rate constant (0.0122 min−1), which is about 5.16 times better than that of TiO2. As a photoanode, TiO2/SnS/MoS2 has the highest photocurrent (0.841 mA cm−2), which is approximately 8.32 times better than those of TiO2. The enhanced photocatalytic and photoelectrochemical performance of TiO2/SnS/MoS2 is ascribed to the Z-scheme mechanism determined by the detection of active species and the synergistic effect of SnS and MoS2 co-decoration.

Control of mat thickness in electrospinning with transparent conductive glass collector

AbstractElectrospinning is a versatile technique for producing micro‐ and nanofibrous mats with great potential in many fields. However, reproducibility remains a key issue for product development. In particular, thickness is an important parameter for controlling electrospun fiber mats. In this study, we developed a method to control the polymer mat thickness during electrospinning. The mat thickness was controlled on the basis of the light transmittance and by using conductive indium tin oxide (ITO) glass connected to ground as a collector. Living cells were seeded on the fiber mat without detaching from the ITO glass, which enabled observation under a microscope and the evaluation of cell behavior. This study indicates that the thickness of the fiber mat can be consistently controlled by monitoring the light transmittance instead of the electrospinning duration and the mat can be easily observed under a microscope. This is expected to be particularly useful in the field of tissue engineering.

Cathodic deposition of SnO2 layers on transparent conductive substrates and their photoelectrochemical activity

Tin dioxide (SnO2) films deposited on transparent conductive substrates have been considered as promising candidates for photoelectrochemical and photovoltaic applications due to their promising properties such as high electron mobility, stability, and favorable band edges positions. Therefore, a simple electrochemical approach based on the cathodic deposition of SnO2 on a conductive glass substrate was proposed. SnO2 layers were obtained by electrodeposition from SnCl2 solution containing HNO3 at various potentials (from −0.6 V to −1.0 V vs. SCE) for various durations (from 5 min to 180 min). The obtained materials were then annealed in air at 400 °C and characterized. The co-deposition of the metallic phase at the most negative potential was confirmed. However, it was successfully converted to the oxide phase by thermal treatment. The photoelectrochemical activity of the materials during illumination with monochromatic light from the range between 250 and 500 nm was studied. The higher photocurrents were generated by annealed layers, and the most promising photoelectrochemical properties were observed for the sample deposited at −0.8 V vs. SCE for 180 min. It is expected that such a simple electrochemical approach can be an effective strategy for the fabrication of highly efficient photoanodes for photoelectrochemical and photovoltaic applications.

Microwave-assisted hydrothermal synthesis of copper selenides (Cu2−x Se) thin films for quantum dots-sensitized solar cells

In this work, copper selenide (Cu2−x Se) thin films were grown on FTO conductive glass substrates using a facile microwave-assisted hydrothermal method. The effects of synthesis parameters such as precursor components and deposition time on the stoichiometry and morphology of the synthesized films were systematically investigated through different techniques including XRD, SEM, and AFM. In order to evaluate the electrochemical catalytic performance of the synthesized copper selenide in electrolyte containing the sulfide/polysulfide redox couple, we assembled liquid-junction quantum dots-sensitized solar cells (QDSSC) using the synthesized copper selenide thin films as counter electrodes and CdSe quantum dots-sensitized mesoporous TiO2 as photoanodes. Under the illumination of one Sun (100 mW cm−2), the QDSSC assembled with the optimal copper selenide CEs (Cu:Se = 1:1) exhibited a power conversion efficiency of 2.07%, which is much higher than that of traditional Pt counter electrode (0.76%).

Detailed analyses on the role of nanobranches in photoelectrochemical performances of multiscale ZnO nanobrushes

In this study, brush-like hierarchical ZnO microrod/nanobranche photoanodes are fabricated via a facile two-step hydrothermal method. The application of the multiscale ZnO microrod backbone formed on a conductive glass substrate allows the growth of ZnO nanobrushes with controllable branch length, which enables detailed studies on the distinctive working mechanism of integrated ZnO microrod backbone and nanobranch structures. The growth and optimization of the uniformly formed secondary nanobranches significantly enhances PEC performance. In addition, the variations in photopotential and charge-carrier transfer are identified through open-circuit potential measurement and electrochemical impedance spectroscopy, to understand the electron–hole transfer kinetics of the ZnO nanobrushes. The results reveal that the distinctive performance of the ZnO nanobrushes originates from the synergetic effect of the ZnO microrod backbone/nanobranches, the subsequent effective charge separation, and enhanced carrier generation in the dominant space-charge region. In particular, the optimum photoelectrode is determined to be that containing the ZnO nanobrushes with nanobranches grown for 5 h, and the corresponding photocurrent density is measured to be 1.68 mA/cm2, which is 136.3% higher than that of the pristine ZnO microrod electrodes.

On the Effect of Thermal Processing on Sn Diffusion and Efficiency Enhancement in Hematite/FTO Photoanodes

The frequently underestimated effects of “in air” thermal treatment processing conditions such as temperature, duration, and heating and cooling rates in the design and efficiency of photoelectrodes fabricated for academic studies onto the most common commercial transparent conductive glass substrate i.e. fluorine-doped tin oxide (FTO) were investigated by XRD, XPS, SEM, conductive AFM, electrochemical impedance spectroscopy (EIS) as well as direct current (DC) and photoelectrochemical (PEC) measurements. The PEC response of Hematite photoanode thin films consisting of short nanorods thermally treated at 400 °C and 800 °C upon fast or extended time conditions is inhibited by factors such as crystallinity, Sn diffusion, or substrate integrity. A “fast” thermal treatment in air at 750 °C provided the best synergy between charge transfer resistance, Sn-diffusion from the FTO substrate, nanorod dimensions, reduced recombination, improved charge separation and minimized substrate damage. This study does offer valuable fundamental and practical insights for a better understanding of the benefits and drawbacks of photoelectrode thermal processing, which is critical for the improvement of the PEC performance-reproducibility relationship for FTO-based solar water splitting systems and devices.

Synergistic Enhancement Properties of a Flexible Integrated PAN/PVDF Piezoelectric Sensor for Human Posture Recognition.

The flexible pressure sensor has attracted much attention due to its wearable and conformal advantage. All the same, enhancing its electrical and structural properties is still a huge challenge. Herein, a flexible integrated pressure sensor (FIPS) composed of a solid silicone rubber matrix, composited with piezoelectric powers of polyacrylonitrile/Polyvinylidene fluoride (PAN/PVDF) and conductive silver-coated glass microspheres is first proposed. Specifically, the mass ratio of the PAN/PVDF and the rubber is up to 4:5 after mechanical mixing. The output voltage of the sensor with composite PAN/PVDF reaches 49 V, which is 2.57 and 3.06 times that with the single components, PAN and PVDF, respectively. In the range from 0 to 800 kPa, its linearity of voltage and current are all close to 0.986. Meanwhile, the sensor retains high voltage and current sensitivities of 42 mV/kPa and 0.174 nA/kPa, respectively. Furthermore, the minimum response time is 43 ms at a frequency range of 1–2.5 Hz in different postures, and the stability is verified over 10,000 cycles. In practical measurements, the designed FIPS showed excellent recognition abilities for various gaits and different bending degrees of fingers. This work provides a novel strategy to improve the flexible pressure sensor, and demonstrates an attractive potential in terms of human health and motion monitoring.

1,4-Bis((9H-Carbazol-9-yl)Methyl)Benzene-Containing Electrochromic Polymers as Potential Electrodes for High-Contrast Electrochromic Devices.

Four 1,4-bis((9H-carbazol-9-yl)methyl)benzene-containing polymers (PbCmB, P(bCmB-co-bTP), P(bCmB-co-dbBT), and P(bCmB-co-TF)) were electrosynthesized onto ITO transparent conductive glass and their spectral and electrochromic switching performances were characterized. The PbCmB film displayed four types of color variations (bright gray, dark gray, dark khaki, and dark olive green) from 0.0 to 1.2 V. P(bCmB-co-bTP) displayed a high transmittance variation (∆T = 39.56% at 685 nm) and a satisfactory coloration efficiency (η = 160.5 cm2∙C−1 at 685 nm). Dual-layer organic electrochromic devices (ECDs) were built using four bCmB-containing polycarbazoles and poly(3,4-ethylenedioxythiophene) (PEDOT) as anodes and a cathode, respectively. PbCmB/PEDOT ECD displayed gainsboro, dark gray, and bright slate gray colors at −0.4 V, 1.0 V, and 2.0 V, respectively. The P(bCmB-co-bTP)/PEDOT ECD showed a high ∆T (40.7% at 635 nm) and a high coloration efficiency (η = 428.4 cm2∙C−1 at 635 nm). The polycarbazole/PEDOT ECDs exhibited moderate open circuit memories and electrochemical redox stability. The characterized electrochromic properties depicted that the as-prepared polycarbazoles had a satisfactory application prospect as an electrode for the ECDs.