An electrochemical microactuator based on highly textured LiCoO2

In this paper we demonstrate a novel electrochemical actuator based on an array of micro-pillars of intercalation compound LiCoO2 with induced crystallographic texture (Lotgering factor f = 0.96) to enhance actuation strain. The highly textured LiCoO2 posts were fabricated by hot-press sintering and subsequent dicing, and the contrived texture facilitated both electrochemical lithiation and resulting actuation strain in the longitudinal direction. Compared with traditional actuator materials, such as piezoceramics, the micro-pillar array of LiCoO2 showed an almost one order higher actuation strain (1.2%) at a low applied voltage (<5 V). The conceptual demonstration outlined in this paper provides a foundation for the design and application of intercalation compounds as novel smart materials

The effect of Nd substitution on the electrical properties of Bi3NbTiO9 Aurivillius phase ceramics

The effect of Nd substitution on the electrical properties of Bi3NbTiO9 Aurivillius phase ceramic

High temperature lead-free relaxor ferroelectric: intergrowth Aurivillius phase BaBi2Nb2O9−Bi4Ti3O12 ceramics

High temperature lead-free relaxor ferroelectric: intergrowth Aurivillius phase BaBi2Nb2O9−Bi4Ti3O12 ceramic

Fabrication and electrical properties of bulk textured LiCoO2

Fabrication and electrical properties of bulk textured LiCoO

Microstructure and electrical properties of Aurivillius phase (CaBi2Nb2O9)1-x(BaBi2Nb2O9)x solid solution

Microstructure and electrical properties of Aurivillius phase (CaBi2Nb2O9)1-x(BaBi2Nb2O9)x solid solutio

Fabrication and electrical properties of bulk textured LiCoO2

Fabrication and electrical properties of bulk textured LiCoO

Thermal depoling of high Curie point Aurivillius phase ferroelectric ceramics

Thermal depoling of high Curie point Aurivillius phase ferroelectric ceramic

Feasibility of using Y₂Ti₂O₇ nanoparticles to fabricate high strength oxide dispersion strengthened Fe-Cr-Al steels

Addition of Al can improve the corrosion resistance of oxide dispersion strengthened (ODS) steels. However, Al reacts with Y2O3 to form large Y-Al-O particles in the steels and deteriorates their mechanical properties. Herein, we successfully prepared Y2Ti2O7 nanoparticles (NPs) by the combination of hydrogen plasma-metal reaction (HPMR) and annealing. Y2Ti2O7 NPs with contents of 0.2 or 0.6 wt.% were then added into the Fe-14Cr-3Al-2W-0.35Ti (wt.%) steel to substitute the conventional Y2O3 NPs by mechanical alloying (MA). The Y2Ti2O7 NPs transformed into amorphous-like structure after 96 h MA. They crystallized with a fine size of 7.4±3.7 nm and shared a semi-coherent interface with the matrix after hot isostatic pressing (HIP) of the ODS steel with 0.6 wt.% Y2Ti2O7. With the increasing Y2Ti2O7 content from 0.2 to 0.6 wt.%, the tensile strength of the ODS steel increased from 1238 to 1296 MPa, which was much higher than that (949 MPa) of the ODS steel added with Y2O3. The remarkably improved mechanical properties of the Al-containing ODS steels were attributed to the increasing number density of Y2Ti2O7 nanoprecipitates. Our work demonstrates a novel route to fabricate high performance ODS steels with both high mechanical strength and good corrosion resistance

Current understanding and applications of the cold sintering process

In traditional ceramic processing techniques, high sintering temperature is necessary to achieve fully dense microstructures. But it can cause various problems including warpage, overfiring, element evaporation, and polymorphic transformation. To overcome these drawbacks, a novel processing technique called “cold sintering process (CSP)” has been explored by Randall et al. CSP enables densification of ceramics at ultra-low temperature (≤ 300 °C) with the assistance of transient aqueous solution and applied pressure. In CSP, the processing conditions including aqueous solution, pressure, temperature, and sintering duration play critical roles in the densification and properties of ceramics, which will be reviewed. The review will also include the applications of CSP in solid-state rechargeable batteries. Finally, the perspectives about CSP is proposed

Low temperature fabrication of hydrangea-like NiCo2S4 as electrode materials for high performance supercapacitors

Hydrangea-like NiCo2S4 as electrode materials for high performance supercapacitors was synthesized by using a facile low temperature (90 °C) two-step hydrothermal technique without surfactant or template. The special hydrangea-like structure and large specific surface area (74.8 m2/g) provided plenty of electro active sites which were beneficial to superior pseudocapacitive performance of NiCo2S4. The supercapacitors performance of NiCo2S4 was investigated by a three-electrode system. NiCo2S4 exhibited high specific capacitance with 1475 F g−1 at a current density of 3 A g−1, and a fairly high rate capacity with 1152 F g−1 at 20 A g−1. These results indicate that low temperature hydrothermal is a very promising method to prepare electrode materials for supercapacitors