Shear-phase early transition metal oxides, mostly of Nb, and comprising edge-and corner-shared metal−oxygen octahedra have seen a resurgence in recent years as fast-charging, low-voltage electrodes for Li + -ion batteries. Mo oxides, broadly, have been less well studied as fast-charging electrodes.Here we examine a reduced Mo oxide, Mo 4 O 11 , that has a structure comprising only corner-connected MoO 4 tetrahedra and MoO 6 octahedra. We show that an electrode formed using micrometer-sized particles of Mo 4 O 11 as the active material can function as a high-rate Li + -ion electrode against Li metal, with a stable capacity of over 200 mAh g −1 at the high rate of 5C. Operando X-ray diffraction (XRD), entropic potential measurements, and ex situ Raman spectroscopy are employed to understand the nature of the charge storage. The crystal structure dramatically changes upon the first lithiation, and subsequent cycling is completely reversible with low capacity fade. It is the newly formed and potentially more layered structure that demonstrates high-rate cycling and small voltage polarization. A space group and unit cell for the new structure is proposed. This finding expands the scope of candidate highrate electrode materials to those beyond the expected Nb-containing shear-phase oxide materials.

A chitosan composite with a vertical array of pore channels is fabricated via an electrophoretic deposition (EPD) technique. The composite consists of chitosan and polyethylene glycol, as well as nanoparticles of silver oxide and silver. The formation of hydrogen bubbles during EPD renders a localized increase of hydroxyl ions that engenders the precipitation of chitosan. In addition, chemical interactions among the constituents facilitate the establishment of vertical channels occupied by hydrogen bubbles that leads to the unique honeycomb-like microstructure; a composite with a porosity of 84%, channel diameter of 488 μm, and channel length of 2 mm. The chitosan composite demonstrates an impressive water uptake of 2100% and a two-stage slow release of silver. In mass transport analysis, both Disperse Red 13 and ZnO powders show a much enhanced transport rate over that of commercial gauze. Due to its excellent structural integrity and channel independence, the chitosan composite is evaluated in a passive suction mode for an adhesive force of 9.8 N (0.56 N cm −2 ). The chitosan composite is flexible and is able to maintain sufficient adhesive force toward objects with different surface curvatures.

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