Rational design of highly efficient bifunctional electrocatalysts based on 3D transition-metal-based materials for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is of great importance for sustainable energy conversion processes. Herein, a novel strategy involving outer and inner structural engineering is developed for superior water splitting via in situ vertical growth of 2D amorphous FePO nanosheets on Ni foam (Am FePO /NF). Careful experiments and density functional theory calculations show that the inner and outer structural engineering contributing to the synergistic effects of 2D morphology, amorphous structure, conductive substrate, and Ni-Fe mixed phosphate lead to superior electrocatalytic activity toward OER and HER. Furthermore, a two-electrode electrolyzer assembled using Am FePO /NF as an electrocatalyst at both electrodes gives current densities of 10 and 100 mA cm at potentials of 1.54 and 1.72 V, respectively, which is comparable to the best bifunctional electrocatalyst reported in the literature. The strategies, introduced in the present work, may open new opportunities for the rational design of other 3D transition-metal-based electrocatalyst through an outer and inner structural control to strengthen the electrocatalytic performance.

(2010) Autophagy was activated in injured astrocytes and mildly decreased cell survival following glucose and oxygen deprivation and focal cerebral ischemia, Autophagy,6:6,[738][739][740][741][742][743][744][745][746][747][748][749][750][751][752][753]

Modulating and constructing interface engineering is an efficient strategy to enhance catalytic activity for water splitting. Herein, a hybrid nanoarray structure of V‐CoP@a‐CeO2, where “a” represents amorphous, integrated into carbon cloth is fabricated for water splitting. The synergy effect between V and CeO2 can increase the electron density of Co atoms at active sites, further optimizing the Gibbs free energy of H* adsorption energy (ΔGH*). Besides, V‐CoP@a‐CeO2 possesses lower water adsorption/dissociation energies, enabling accelerated reaction kinetics in alkaline media. As expected, the V‐CoP@a‐CeO2 exhibits superior performance toward the hydrogen evolution reaction and the oxygen evolution reaction. More importantly, a two‐electrode electrolyzer combined with an electrocatalyst of V‐CoP@ a‐CeO2 only demands that voltages of electrolytic cell are 1.56 and 1.71 V to achieve the current densities of 10 and 100 mA cm−2, respectively. This work provides guidance for the design or optimization of materials for water electrolysis and beyond.

Polysaccharide is an abundant and reproducible natural material that is biocompatible and biodegradable. Polysaccharide and its derivatives also possess distinctive properties such as hydrophilicity, mechanical stability, as well as tunable functionality. Polysaccharide‐based hydrogels can be constructed via the physical and/or chemical crosslinking of polysaccharide derivatives with different functional molecules, as porous network structures or nanofibrillar structures. This review discusses the biomedical applications of polysaccharide‐based hydrogels containing native polysaccharides, polysaccharide derivatives, and polysaccharide‐composite hydrogels. Recent works on the fabrication, physical properties, advanced engineering, biomedical applications of cellulose‐, chitosan‐, alginate‐, and starch‐based hydrogels are also elaborated. Such porous swelling scaffolds exhibit great advantages at the interface of a negative pressure system such as wound dressing. In addition, the authors also discuss and summarize the exemplary research works of these hydrogels in the applications of drug release, wound dressing, and tissue engineering. Finally, challenges and future perspectives about the development of polysaccharide‐based hydrogels are discussed.

Triboelectric nanogenerators and sensors can be applied as human− machine interfaces to the next generation of intelligent and interactive products, where flexible tactile sensors exhibit great advantages for diversified applications such as robotic control. In this paper, we present a self-powered, flexible, triboelectric sensor (SFTS) patch for finger trajectory sensing and further apply the collected information for robotic control. This innovative sensor consists of flexible and environmentally friendly materials, i.e., starch-based hydrogel, polydimethylsiloxane (PDMS), and silicone rubber. The sensor patch can be divided into a two-dimensional (2D) SFTS for in-plane robotic movement control and a one-dimensional (1D) SFTS for out-of-plane robotic movement control. The 2D-SFTS is designed with a grid structure on top of the sensing surface to track the continuous sliding information on the fingertip, e.g., trajectory, velocity, and acceleration, with four circumjacent starchbased hydrogel PDMS elastomer electrodes. Combining the 2D-SFTS with the 1D-SFTS, three-dimensional (3D) spatial information can be generated and applied to control the 3D motion of a robotic manipulator, and the real-time demonstration is successfully realized. With the facile design and very low-cost materials, the proposed SFTS shows great potential for applications in robotics control, touch screens, and electronic skins.