Long Bei, Balogun Muhammad-Sadeeq, Luo Lei, Luo Yang, Qiu Weitao, Song Shuqin, Zhang Lei, Tong Yexiang
The Key Lab of Low-Carbon Chemistry and Energy Conservation of Guangdong Province, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, P. R. China.
MOE of the Key Laboratory of Bioinorganic and Synthetic Chemistry, KLGHEI of Environment and Energy Chemistry, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, P. R. China.
Small. 2017 Nov;13(41). doi: 10.1002/smll.201702081. Epub 2017 Sep 12.
Recently, researchers have made significant advancement in employing transition metal compound hybrids as anode material for lithium-ion batteries and developing simple preparation of these hybrids. To this end, this study reports a facile and scalable method for fabricating a vanadium oxide-nitride composite encapsulated in amorphous carbon matrix by simply mixing ammonium metavanadate and melamine as anode materials for lithium-ion batteries. By tuning the annealing temperature of the mixture, different hybrids of vanadium oxide-nitride compounds are synthesized. The electrode material prepared at 700 °C, i.e., VM-700, exhibits excellent cyclic stability retaining 92% of its reversible capacity after 200 cycles at a current density of 0.5 A g and attractive rate performance (220 mAh g ) under the current density of up to 2 A g . The outstanding electrochemical properties can be attributed to the synergistic effect from heterojunction form by the vanadium compound hybrids, the improved ability of the excellent conductive carbon for electron transfer, and restraining the expansion and aggregation of vanadium oxide-nitride in cycling. These interesting findings will provide a reference for the preparation of transition metal oxide and nitride composites as well.
最近，研究人员在将过渡金属化合物杂化物用作锂离子电池的负极材料以及开发这些杂化物的简单制备方法方面取得了重大进展。为此，本研究报告了一种简便且可扩展的方法，通过简单地混合偏钒酸铵和三聚氰胺作为锂离子电池的负极材料，制备封装在无定形碳基质中的氧化钒 - 氮化物复合材料。通过调节混合物的退火温度，合成了不同的氧化钒 - 氮化物化合物杂化物。在700°C下制备的电极材料，即VM - 700，表现出优异的循环稳定性，在0.5 A g的电流密度下循环200次后保留其可逆容量的92%，并且在高达2 A g的电流密度下具有吸引人的倍率性能（220 mAh g）。优异的电化学性能可归因于钒化合物杂化物形成的异质结的协同效应、优异导电碳改善的电子转移能力以及抑制氧化钒 - 氮化物在循环中的膨胀和聚集。这些有趣的发现也将为过渡金属氧化物和氮化物复合材料的制备提供参考。
