Superior lithophilicity for the 3D host is essential to enable both uniform molten lithium (Li) infusion during synthesis and a low Li nucleation barrier during cycling. The wetting behavior between the host surface and molten Li can be reasonably predicted by the typical Wenzel model. Herein, inspired by the model, a lotus-leaf-like carbon nanotube (CNT)/NiO spheres hybrid structure is employed to improve the wettability and regulate Li plating/stripping. First, the CNTs interweave to form a highly conductive and robust sponge with accelerated Li + transport and reinforced stability. Second, the embedded NiO microspheres possess the Li-active nature. More importantly, the surface roughness caused by nano-sized protuberances over its surface further stronger the lithiophilicity. By the in situ optical microscope and calculations, this multistage structure is proven to homogenize the Li deposition and inhibit dendrite growth. As a result, the composite anode enables excellent cycling performance at both symmetric and full cells. This design of micro/ nanostructured host provides a new perspective on the development of an excellent wettable host for Li-metal anode.

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Conductive hydrogels (CHs) are ideal electrolyte materials for the preparation of flexible supercapacitors (FSCs) due to their excellent electrochemical properties, mechanical properties, and deformation restorability. However, most of the reported CHs are prepared by the chemical crosslinking of synthetic polymers and thus usually display the disadvantages of poor self-healing abilities and nonadaptability at environmental temperatures, which greatly limits their application. To overcome these problems, in the present work, we constructed a sodium alginate–borax/gelatin double-network conductive hydrogel (CH) by a dynamic crosslinking between sodium alginate (SA) and borax via borate bonds and hydrogen bonding between amino acids in gelatin and SA chains. The CH displays an excellent elongation of 305.7% and fast self-healing behavior in 60 s. Furthermore, a phase-change material (PCM), Na2SO4·10H2O, was introduced into the CH, which, combined with the nucleation effect of borax, improved the ionic conductivity and temperature adaptability of the CH. The flexible supercapacitor (FSC) assembled with the obtained CH as the electrolyte exhibits a high specific capacitance of 185.3 F·g–1 at a current density of 0.25 A·g–1 and good stability with 84% capacitance retention after 10 000 cycles and excellent temperature tolerance with a resistance variation of 2.11 Ω in the temperature range of −20–60 °C. This green CH shows great application potential as an electrolyte for FSCs, and the preparation method can be potentially expanded to the fabrication of self-repairing FSCs with good temperature adaptabilities.

The multimolecular complexes formed between 2,4,6,8,10,12-hexanitro-2,4,6,6,8,10,12-hexaazaisowurtzitane (CL-20) and nitropyrazole compounds were investigated using B3LYP-D3/6-311G(d,p) and B97-3c methods. CL-20 in these complexes was surrounded by methyl, nitro, and amino derivatives of 4-nitropyrazole. The influence of substituents on the molecular electrostatic potential distribution of nitropyrazoles was investigated to figure out the potential electrostatic interaction sites. For the complex, the O···H hydrogen bond was popular in the intermolecular interactions, and dispersion interaction played an essential role, especially in C x /CL-20 multimolecular complexes. Trigger bond analysis showed that their strength increased upon the formation of intermolecular weak interactions. Nitro group charge calculations stated that the negative charge on almost all nitro groups showed a significant increase. Therefore, the sensitivity of CL-20 seemed to be lower than the original. In addition, the transfer of electron density between CL-20 and nitropyrzoles in complexes was investigated, revealing the influence of weak interactions on the electron density of CL-20.