Recently, electrical stimulation as a physical stimulus draws lots of attention. It shows great potential in disease treatment, wound healing, and mechanism study because of significant experimental performance. Electrical stimulation can activate many intracellular signaling pathways, and influence intracellular microenvironment, as a result, affect cell migration, cell proliferation, and cell differentiation. Electrical stimulation is using in tissue engineering as a novel type of tool in regeneration medicine. Besides, with the advantages of biocompatible conductive materials coming into view, the combination of electrical stimulation with suitable tissue engineered scaffolds can well combine the benefits of both and is ideal for the field of regenerative medicine. In this review, we summarize the various materials and latest technologies to deliver electrical stimulation. The influences of electrical stimulation on cell alignment, migration and its underlying mechanisms are discussed. Then the effect of electrical stimulation on cell proliferation and differentiation are also discussed.

The revival of the Na‐ion battery concept has prompted intense research activities toward new sustainable Na‐based insertion compounds and their implementation in full Na‐ion cells. Efforts are parted between Na‐based polyanionic and layered compounds. For the latter, there has been a specific focus on Na‐deficient layered phases that show cationic and anionic redox activity similar to a Na0.67Mn0.72Mg0.28O2 phase. Herein, a new alkali‐deficient P2‐Na2/3Mn7/9Zn2/9O2 phase using a more electronegative element (Zn) than Mg is reported. Like its Mg counterpart, this phase shows anionic redox activity and no O2 release despite evidence of cationic migration. Density functional theory (DFT) calculations show that it is the presence of an oxygen nonbonding state that triggers the anionic redox activity in this material. The phase delivers a reversible capacity of 200 mAh g−1 in Na‐half cells with such a value be reduced to 140 mAh g−1 in full Na‐ion cells which additionally shows capacity decay upon cycling. These findings establish Na‐deficient layered oxides as a promising platform to further explore the underlying science behind O2 release in insertion compounds based on anionic redox activity.

A robust, self-healing superhydrophobic poly(ethylene terephthalate) (PET) fabric was fabricated by a convenient solution-dipping method using an easily available material system consisting of polydimethylsiloxane and octadecylamine (ODA). The surface roughness was formed by self-roughening of ODA coating on PET fibers without any lithography steps or adding any nanomaterials. The fabric coating was durable to withstand 120 cycles of laundry and 5000 cycles of abrasion without apparently changing the superhydrophobicity. More interestingly, the fabric can restore its super liquid-repellent property by 72 h at room temperature even after 20000 cycles of abrasion. Meanwhile, after being damaged chemically, the fabric can restore its superhydrophobicity automatically in 12 h at room temperature or by a short-time heating treatment. We envision that this simple but effective coating system may lead to the development of robust protective clothing for various applications.

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Nowadays, transition-metal oxides are regarded as the most potential materials for the supercapacitor and electrocatalyst. However, the poor electrical conductivity and insufficient active sites limited their development in various fields. Herein, we report the method of phosphorous-doped NiCo 2 O 4 (named as P-NCO) prepared by the two-step strategy: the NiCo 2 O 4 nanostructure is grown on the nickel foams by hydrothermal treatment and subsequently phosphatized in a tube furnace. Successfully, the rich oxygen vacancies and the P element introduced into the NiCo 2 O 4 structure obviously improve the electrical conductivity, and the resulting P-NCO NWs/NF material shows an ultrahigh specific capacitance of 2747.8 F g −1 at 1 A g −1 and a prominent rate performance (maintain 50% at 100 A g −1 ). Furthermore, the assembled P-NCO NWs/NF//RGO asymmetric supercapacitor has an energy density of 28.2 W h kg −1 even at a high power density of 7750.35 W kg −1 . After 10,000 cycles, the capacitance still also has an 88.48% retention rate. As an electrocatalyst, P-NCO NWs/NF has an excellent hydrogen evolution reaction (55 mV at 10 mA cm −2 ) and oxygen evolution reaction (300 mV at 10 mA cm −2 ) activities in 1 M KOH solution. This study provides an effective strategy to prepare multifunctional materials.

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Decoupling the effect of vacancies and electropositive cations on the anionic redox processes in Na based P2-type layered oxides. (2020) Energy Storage Materials, 31. 146-155.

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