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MoO 3–x nanobelts (MoO 3-x NBs) were synthesized via a novel “sauna reaction”, providing us an opportunity for illustrating the effect of oxygen vacancies (OVs) on its largely enhanced electrochemical performance. Very exciting, the MoO 3-x NBs exhibits much superior performance with 400 and 267 mAh g −1 , which is about three times larger than that of the pristine MoO 3 NBs (123 and 84 mAh g −1 ), at the current densities of 100 and 200 mA g −1 , respectively. Notably, the OVs and the resulting improved electrical conductivity could be used to account for their largely enhanced specific capacity and rate properties. On one hand, OVs lowered the energy barrier of Li + into the intralyer of MoO 6 octahedron sheet layer and the interlayer of MoO 3-x , and provided extra lithium storage sites of MoO 3 during discharge-charge process. On the other hand, the improved conductivity of MoO 3-x provided efficient electron transport pathways. The results show that OVs control can be a promising strategy for enhancing high-performance Mo-based electrodes by taking advantage of structural characteristics of multiple oxide sates of Mo elements. This study not only provides a new method for the preparation of MoO 3-x with rich OVs using a simple, environmentally friendly “sauna reaction”, but also indicates the importance of OVs in the largely enhanced electrochemical performance in MoO 3-x NBs, which may shed some light on the future development of electrode materials of lithium-ion batteries (LIBs).

Recently, chitosan is discovered as a most abundant natural polymer, which is not only a lightweight, low-cost, sustainable resource with potentials in energy transformation, but also biocompatibility and biodegradability. In this article, they investigated a highly biocompatible chitosan-based electro-active polymer (C-Polymer) actuator composed of multiwall carbon nanotube, ionic liquid, and polymer-supported chitosan. As a result, after the changed MCNTs rate (20%, 40%, 60%, and 80%) in the electrode membrane, actuation properties of C-polymer actuator behaved a great enhancement. With the increase of the ratio of MCNTs, the specific capacitance and the electrode resistance were obviously improved, which were 2.02 F/g and 1.32 Ω under rate of 80%, and the maximum displacement and the response speed behaved a peak value of 7 mm (80%) and 0.032 mm/s (80%). Interestingly, it also showed an increasing for the maximum blocking force and response speed under the ratio of 80%, which presented the maximum value of 6.80 mN and 0.11 mN/s. In order to analyze causes for this enhancement, a valid generated strain values were calculated to evaluate the strain on the electrode layer. However, it is exhibited that the generated strain was very small, which almost kept in the value of 0.5%, and it was unrelated to Young's modulus. Moreover, they also found that the resistance and the specific capacitance could strongly affect the electromechanical properties of C-polymer actuator with different rate of MCNTs, and revealed a vital potential Ramsay rule between the electrochemical properties and electromechanical properties of C-polymer actuator. POLYM. COMPOS., 2016. © 2016 Society of Plastics Engineers

For large amounts of transition metal oxides, sulfides and carbon groups (IVA), the pulverization of electrode materials in lithium-ion batteries (LIBs) is always a serious and common problem due to volume expansion and stress accumulation resulting from phase transformation or alloying during the charge–discharge process, which leads to capacity fading and thus limits the cycling performance of LIBs. To solve these problems, conventionally, the rational design of electrode materials is needed. Here in this work, we report the synthesis of a novel anode material, hexagonal H4.5Mo5.25O18·(H2O)1.36 microrods (HMs) via a simple hydrothermal method. During the lithium-ion insertion/desertion process of the HMs, it was found that the HMs are first drastically transformed into Li2MoO4 nanotubes and then Li2MoO4 nanowire clusters embedded in amorphous sphere cages with a Li2O matrix, Mo metal and SEI thin film. Surprisingly, we discovered that the HMs exhibited extraordinary long-life cyclability with an unusual phenomenon: the specific capacity first decreased and then increased. The outstanding electrochemical performance could be explained by the formation of intermediate phase Li2MoO4 nanowires and amorphous sphere cages, which can maintain the lithium-ion paths and electronic transport, and prohibit the mechanical and chemical degradation of the electrode materials. The results show that the pulverization of the HM anode materials induced by lithium-ion insertion–extraction played a trigger role in the formation of a continuous pulverization film. Accordingly, a “damage-reconstruction” model based on ex situ XRD and FESEM analyses combined with ex situ XPS, FTIR and TEM characterizations of the charge–discharge process was proposed to explain such an unusual and intriguing finding. Compared with the conventional method for protecting electrode materials from pulverization, the robust continuous gel-like pulverization film containing a unique combination of intermediate phase and amorphous sphere cages provides a new insight into the mechanism for the extraordinary long-term cyclability of electrode materials.

The electromechanical properties of ionic polymer metal composites (IPMCs) are affected by many factors that are closely related to different physical and chemical preparation processes. This article focuses on the effects of chemical plating time on the electromechnical properties of IPMCs. First, a laminated electrode model, composed of a middle layer and a surface electrode layer, is presented in order to understand the factors affecting the electromechanical properties of IPMCs. Subsequently, the electromechanical properties were further performed by changing the chemical plating time of the polymer samples, and the impact effects were obtained by morphology characteristic analysis. The experiments revealed the mechanisms that lead to a decrease in surface electrode thickness under different chemical plating times as well as a decline in electromechanical properties.

Ionic actuators have attracted attention due to their remarking large strain under low-voltage stimulation. Because the actuation performance is mainly dominated by the electrochemical and electromechanical processes of the electrode layer, the electrode materials and structure are crucial. In this manuscript, we report a highly biocompatible polymer actuator, which consists of multiwalled carbon nanotubes (MCNTs) film as double electrode layer and an electrolyte layer equipped with a chitosan polymer skeleton and an ionic liquid. The electrochemical properties of chitosan polymer actuator under various content of MCNTs were presented by SEM, cyclic voltammetry, and alternate current impedance. Results represented that MCNTs as a reinforcing agent in the chitosan polymer actuator strongly affected the electromechanical energy efficiency. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers

In this manuscript, we present a highly biocompatible polymer actuator, which consists of MCNT film as double electrode layer and a electrolyte layer equipped with a chitosan polymer skeleton and an ionic liquid. First, the fabrication method of C-polymer actuator was developed in our current frame. Subsequently, by the measurement of the electromechanical properties, C-polymer actuator showed good deflection deformation and force output characteristics. Moreover, the alternate current impedance and the cyclic voltammeter analysis results demonstrated the electrode layer has a low impedance (1.32 Ω) and a high double-layer specific capacitance (2.02 F/g). As a result, our C-polymer actuator shows no back-relaxation phenomenon, and the bending deformation was considered to be attributed to the volume-change of the electrolyte layer in the cathode and the anode. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers

This article primarily focuses on the tandem combination method and parallel combination method fabricating Muscle-like linear actuator based on ionic polymer metal composites. First, according to the proposed combination methods, muscle-like linear actuator model was further to manufacture by adopting Bi-film linear actuator described in our previous work. Subsequently, a series of experiments were done to investigate the performance characteristics of muscle-like linear actuator including of force output capability and motor coordination capability. Also, some evaluation methods were established to analyze the experimental effect. Finally, experiment results revealed the exiting performance differences through comparing with performance characteristics between the two combination methods, and its relevant combination mechanism was proceeded to clarified. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers

Focusing on the existing issues of ionic polymer metal composites (IPMC), for example, little force output and swing motion, and the applied requirements in the biomimetic artificial muscles using as the actuators, under the current framework, a muscle-like linear actuator based on the combination of Bi-IPMC linear actuator unit, whose experimental characteristics have been discussed in our previous work, was fabricated. The performance investigation showed that it can generate a linear movement type like artificial muscle, and there is an prominent improvement of force output capabilities compared with Bi-IPMC linear actuator unit. Also, based on the 3D printing technique, a bionic jumping robot was experimented using the fabricating muscle-like linear actuator, and the experimental result was validated against the feasibility of muscle-like linear actuator. POLYM. COMPOS., 2015. © 2015 Society of Plastics Engineers