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Summary Polyaniline‐derived N‐doped carbon‐composited Na3V2(PO4)3 (NVP@NC) are synthesized by a rheological phase reaction followed by calcination. The NVP@NC composite displays improved cycling and rate properties. Its discharge capacity remains 118.7 mAh g−1 at the 400th cycle at 0.3 C. It also obtains invertible capacities of 93.7 and 91.1 mAh g−1 at 5 and 10 C after 1000 cycles, with capacity retention rates of 92.7% and 98.4%, respectively. These enhanced results due to the N‐doped carbon layer (NC), which restrains the expansion and deformation of the crystal structure, reduce the transport length of sodium ion and electrons and improves the electroconductibility of NVP.

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(1) The studies on the influence of rainfall on slope stability mainly focus on rainfall characteristics and the variation of strength parameters. Few studies pay attention to the micro structure changes of rock mass under long-term rainfall conditions, and the influence of failure mode. (2) Based on nuclear magnetic resonance (NMR) and electron microscopic imaging (Emmi) technology, the micro structure changes and macro deformation characteristics of the schist, under long-term immersion in different liquids are analyzed. (3) After soaking in the deionized water, the uniaxial compression strength of the intact specimen is slightly lower than that of the untreated specimens, but the test process in the elastic compression stage is considerably prolonged, and the failure modes show both shear and slip at the same time. While after soaking in acid solution, the fracture of rock samples with initial cracks can be obviously reduced and healed, which is consistent with the change of micro pore structure. The uniaxial strength and modulus of the intact samples are significantly lower, and only slip failure mode occurred. (4) It shows that water–rock interaction is an important factor influencing the stability of slope besides the external rainfall force, which affects the structural characteristics and mechanical properties of rock.

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