Nanostructure engineering has been proved to be an efficient approach for improving electrochemical properties for energy storage by accommodating volume changes, facilitating rapid mass transport paths, and enlarging ion storage sites and interfaces. The well‐designed fine nanostructures, unfortunately, are usually destroyed during long‐term cycles and ultimately lose their structural advantages. Herein, stimulated by the extraordinary structural stability, robust mechanical properties, and salient ventilation capacity of natural honeycomb species, bioinspired heterogeneous bimetallic Co–Mo oxide (CoMoOx) nanoarchitectures assembled from 2D nanounits are successfully fabricated via a molybdenum‐mediated self‐assembly strategy for improving the rate capability of electrochemical lithium storage devices. Owing to the robust structural stability and the ultrathin 2D wall structure, CoMoOx nanostructures present well‐maintained honeycomb‐like structure, rapid capacitive insertion–desertion behaviors, and thus significantly enhanced lithium ion storage performance at high rates (5.0 A g−1). It is also revealed that the reversible transition of cobalt and molybdenum phases closely associated with the ultrathin 2D wall structures greatly contribute to the outstanding electrochemical lithium storage performances. This attractive integration of structural and functional advantages achieved by learning from nature offers new insights into the design of cost‐effective electrode materials for high‐performance energy devices.

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Hydrotalcites of formula Mg 6 (Al,Fe) 2 (OH) 16 (CO 3 )·4H 2 O formed by intercalation with the carbonate anion as a function of divalent/trivalent cationic ratio have been successfully synthesised. The XRD patterns show variation in the d-spacing attributed to the size of the cation. Raman and infrared bands in the OH stretching region are assigned to (1) brucite layer OH stretching vibrations, (2) water stretching bands and (3) water strongly hydrogen bonded to the carbonate anion. Multiple (CO 3 ) 2− symmetric stretching bands suggest that different types of (CO 3 ) 2− exist in the hydrotalcite interlayer. Increasing the cation ratio (Mg/Al,Fe) resulted in an increase in the combined intensity of the two Raman bands at around 3600 cm −1 , attributed to Mg-OH stretching modes, and a shift of the overall band profile to higher wavenumbers. These observations are believed to be a result of the increase in magnesium in the structure. Raman spectroscopy shows a reduction in the symmetry of the carbonate, leading to the conclusion that the anions are bonded to the brucite-like hydroxyl surface and to the water in the interlayer. Water bending modes are identified in the infrared spectra at positions greater than 1630 cm −1 , indicating that water is strongly hydrogen bonded to both interlayer anions and the brucite-like surface.

In this work, the effects of the concentrations of Cu (II), Zn (II) and Sn (II) ions in electrolytic bath solution on the properties of electrochemically deposited CuZnSn (CZT) films were investigated. The study of the composition of the CZT film has shown that the metallic content (relative atomic ratio) in the film increased linearly with the increase of the metal ion concentration. It is the first time that the relationship of the compositions of the alloy phases in the co-electrodeposited CZT film with the concentration of metal ions was revealed. The results have confirmed that the formantion and content of Cu6Sn5 and Cu5Zn8 alloy phases in the film were directly controlled by the concentration of Cu (II). SEM measurements have shown that Sn (II) had significant impacts on the film morphology which became more porous as a result of the bigger nucleation size of tin. The changes of surface properties of the films was also confirmed by chronoamperometry characteristic (i -t) deposition curve. By optimization of the metal ions concentrations in the electrolyte solution, a copperpoor and zinc-rich kesterite Cu2ZnSnS4 (CZTS) film was synthesized by sulfurization of the deposited CZT film. The solar cell with the CZTS film showed an energy conversion efficiency of 2.15% under the illumination intensity of 100 mW cm -2 .