Properties of chemical solution deposited polycrystalline neodymium-modified Bi4Ti3O12

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The global transition to sustainable energy systems requires breakthroughs in electrochemical storage technologies that are not only safe but also resource efficient. Solid-state batteries (SSBs), which use superionic solid electrolytes (SEs) instead of flammable liquid electrolytes, are at the forefront of this transformation. In general, SEs promise increased safety, access to high-voltage cathode and metal anode chemistries, and new avenues for circular design and recyclability. However, to reach their f

Spacecraft electrostatic discharge is a type of surface discharge in vacuum which is commonly known as vacuum surface flashover, posing a significant threat to the safe operation of spacecraft solar cells. This numerical study investigates vacuum surface flashover on spacecraft solar cells triggered by an inverted potential gradient (IPG), using particle-in-cell simulations. Incorporating the realistic solar cell structure [room temperature vulcanized (RTV) adhesive, cover glass, and metal interconnector] a

We have successfully demonstrated the fabrication of self-actuating multilayer NEMS resonators including cantilevers and double clamped beams. Resonant sensors are widely used as precision mass sensors for the detection and quantification of small concentration of analyte molecules in a gaseous solution or bacteria from biological sample which requires extremely high mass sensitivity and responsivity of the resonant sensor. Nanofabrication techniques have enabled the use of ultrathin layers for the fabricat

The hydrothermal synthesis of SrTiO3 in a Sr(OH)(2)/NaOH solution by reaction of four different single crystalline titanium precursors (anatase, rutile, sodium titanate, and hydrogen titanate) having the same nanowire morphology was investigated under stag ...

Conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) doped with iron(III) tris-p-toluenesulfonate (PEDOT:Tos) having metallic conductivity was coated onto fluorine-doped tin oxide (FTO) glass and plain glass substrates and used as a counter electrode (CE) in a dye-sensitized solar cell (DSC) with a [Co(bpy)3]3+/2+ complex redox shuttle. DSCs with PEDOT:Tos/glass CE yielded power conversion efficiencies (PCE) of 6.3%, similar to that of DSCs with platinized FTO glass CE (6.1%). The PEDOT:Tos-based cou

RF microelectromechanical systems (MEMS) capacitive switches for two different dielectrics, aluminum nitride (AlN) and silicon nitride (Si3N4), are presented. The switches have been characterized and compared in terms of DC and RF performance (5-40 GHz). Switches based on AlN have higher down-state capacitance for similar dielectric thicknesses and provide better isolation and smaller insertion losses compared to Si3N4 switches. Experiments were carried out on RF MEMS switches with stiffening bars to preven

Within the framework of a project consisting in developing a haptic keyboard, each key is aimed to be controlled individually in position and force. Small sized actuators has already been designed and integrated in a 64 keys force feedback keyboard. The project goal is to develop a new self-sensing method to determine the key position without adding any extra sensor. Sensorless techniques are already used in motor control but still represent a challenge in actuators drives. The method could be applied to nu

Stress induced ferroelastic switching may represent an efficient toughening mechanism in piezoelectric-ferroelectric ceramics. During the crack propagation, the high tensional stresses at the crack tip can be partially released by the reorientation of 90 degree domains from along to perpendicular to the propagation direction. Compared to the phase transformation approach (inclusion of zirconia particles in the metastable tetragonal phase) this mechanism is not expected to reduce the piezoelectric properties

We calculate from first principles the nonlinear piezoelectric response of ferroelectric PbTiO3 for the case of a polarization-enhancing electric field applied along the tetragonal axis. We focus mainly on the case of fixed in-plane lattice constants, corr ...

Nanocomposite thin films exhibit interesting optical properties which differ from those of the pure constituents. Effective medium theories are used to model the dielectric function of the nanocomposite materials. We give an introduction to the theories of ...

Over the past fifteen years dye-sensitised nanocrystalline solar cells have been the subject of intense research and development efforts. These systems provide a technically and economically credible alternative to classical p-n junction solar cells, reaching over 10 % certified efficiency under standard solar illumination conditions (AM 1.5, 1000 W/m2). Recently, the liquid electrolyte, commonly used in these dye-sensitised solar cells, could successfully be replaced by a novel solid hole-conducting materi

Polymeric precursor solution (Pechini method) was used to deposit LiNbO3 thin films by spin-coating on (100) silicon substrates. X-ray diffraction data of thin films showed that the increase of oxygen flow promotes a preferred orientation of (001) LiNbO3 planes parallel to the substrate surface. Surface roughness and grain size, observed by atomic force microscopy, change also with oxygen flow.

The structure of the antiphase domain boundaries of strontium titanate SrTiO3 that exist at temperatures below the antiferrodistortive transition, is analyzed. It is found that some boundaries are similar to Neel domain walls, as an additional component of the order parameter develops within them. We show quantitatively that at low temperatures, typically below similar to 40 K, such boundaries become unstable with respect to the development of a ferroelectric polarization. This ferroelectric transition migh

A unified approach for analysis of polarization fatigue and size effects on ferroelectric switching in relationship with injection and entrapment of charge at the interfacial layer of the ferroelectric film is developed. The proposed model suggests that an enhancement of the entrapped charge relaxation at the interfaces has a positive impact on both the polarization fatigue and size effects. This concept is implemented experimentally by introducing a thin conductive oxide (RuO2) layer into the top interface

The mechanical response of piezoelectric cantilever beams actuated by sol-gel- derived lead zirconium titanate (PZT) thin film is reported. Small multilayered beams are used to analyse the converse piezoelectric effect and to measure the mechanical deflection of the beams with a standard interferometry method. Interferometric displacement measurements, electrical measurements and finite- element simulations are reported to determine the piezoelectric coefficient d(31) of the PZT thin film.

We fabricated and characterized a micromotor driven by a piezoelectric PZT (PbZrxTi1-xO3) thin films. Sputter and sol-gel techniques have been applied for the deposition of the PZT films onto a silicon stator membrane, which was 20 to 30 µm thick and had a diameter of 4 mm. The amplitudes of the membrane deflections are as large as 800 nm/V at the first resonance (26 kHz), and 60 nm/V at 1 Hz. The operation of the motor was obtained at 1 to 3 Vrms, with speeds of up to 200 rpm at 1.1 Vrms and torques of 35

Properties of chemical solution deposited polycrystalline neodymium-modified Bi4Ti3O12

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2026 roadmap on next-generation solid electrolytes for battery applications

Numerical investigation of vacuum surface flashover triggered by inverted potential gradient on solar cells using particle-in-cell method

Design and Fabrication of Multilayer Piezoelectric NEMS Resonators

Hydrothermal Synthesis of SrTiO3: Role of Interfaces

Understanding interfacial charge transfer between metallic PEDOT counter electrodes and a cobalt redox shuttle in dye-sensitized solar cells

RF MEMS Shunt Capacitive Switches Using AlN Compared to Si3N4 Dielectric

Force feedback keyboard: self sensing

PFM investigation of stress induced ferroelastic switching in piezoelectric bulk ceramics

First-principles study of high-field piezoelectricity in tetragonal PbTiO3

Optical properties of metal-doped carbon based nanocomposite thin films: Comparing experiment to effective medium theories

Nanoparticle sensitisation of solid-state nanocrystalline solar cell

Influence of oxygen flow on crystallization and morphology of LiNbO3 thin films

Prediction of a low-temperature ferroelectric instability in antiphase domain boundaries of strontium titanate

Charge relaxation at the interfaces of low-voltage ferroelectric film capacitors: Fatigue endurance and size effects

Piezoelectric cantilever beams actuated by PZT sol-gel thin film

Micromachined PZT thin film actuators for micromotors