Tailoring of hierarchical MnMoO4/C nanocauliflowers for high-performance lithium/sodium ion half/full batteries

Abstract

• Hierarchical MnMoO 4 /C nanocauliflowers are successfully fabricated. • Structure engineering and surface modification are simultaneously achieved. • MnMoO 4 /C nanocauliflowers exhibit excellent lithium/sodium storage performance. • MnMoO 4 /C nanocauliflowers can be successfully applied to Li/Na ion full cells. Metal molybdates inherit the characteristics of polyoxometalates (POMs) and have been widely used in the fields of catalysis, photoluminescence and energy storage. However, well construction of hierarchical molybdate nanostructures towards superior performance has still retained a critical challenge. Herein, hierarchical manganese molybdate (MnMoO 4 ) nanocauliflowers are tailored from aggregated microrods utilizing dopamine as a scissor at room temperature. Meanwhile, a uniform and robust carbon coating layer can be introduced after a simple calcination. The fabricated MnMoO 4 /C nanocauliflowers exhibit excellent electrochemical properties as anodes for both lithium/sodium ion half/full batteries. The boosted discharge specific capacities and rate capabilities of MnMoO 4 /C (994 mAh g −1 at 0.1 A g −1 and 487 mAh g −1 at 2.0 A g −1 for lithium ion battery and 296 mAh g −1 at 0.1 A g −1 and 148 mAh g −1 at 2.0 A g −1 for sodium ion battery) are better than those of bare MnMoO 4 . Notably, the stable and sustainable cyclic property with 1500 times for lithium ion battery and 5000 times for sodium ion battery without obvious capacity fading is much superior to the state-of-art results of many other reported molybdates. This simple yet effective strategy demonstrates the feasibility of simultaneous structure engineering and surface modification of molybdates.