近日，实验室曾凡焱老师，侯朝辉老师通过简单的自聚合和煅烧工艺开发了一种耐用的蛋黄壳结构，其中亚纳米级无定形氧化钒（V-O）键合在N掺杂碳纳米球（A-VOxC/N-C）中。作为SIB阳极，该复合材料具有大可逆容量（491.6 A g^-1时为0.05 mAh g^-1）、高倍率能力和超长循环稳定性（246.4 mAh g^-1，在96.6 A g^-130000下循环20次后容量保持率为0.1%）的论文发表在Composites Part B-Engineering。

The energy density of sodium-ion batteries (SIBs) reported so far is still low, which weakens their competi-tiveness in practical applications. Cluster engineering and sub-nanometric design are effective strategies for rapid and efficient storage of alkaline ions. Herein, a durable yolk-shell architecture is developed via a facile self-polymerization and calcination process, in which the sub-nanometric amorphous vanadium-oxide (V-O) clus-ters are bonded in N-doped carbon nanospheres (A-VOxC/N-C). As a SIB anode, the composite delivers a large reversible capacity (491.6 mAh g^-1 at 0.05 A g^-1), high-rate capability and ultra-long cyclic stability (246.4 mAh g^-1 with 96.6% capacity retention after 30000 cycles at 20.0 A g^-1). In addition, the full cell also exhibits great potential for practical applications. The detailed structural characterizations and density functional theory (DFT) calculations suggest that the amorphous clusters without grain boundaries are crucial for the creation of abundant active sites and highly isotropic channels, as well as the reduction of Na-intercalation stress. The yolk-shell N-C has the structural advantages of flexible cavity, strong bonding force and large spatial constraint, which can effectively alleviate volume changes and strengthen structural stability. In view of these, this study can provide guidance for the design of sub-nanometric clusters and their potential applications in alkaline ion batteries.

论文题目：Sub-nanometric amorphous V-O clusters without grain boundaries bonded in yolk-shell carbon nanospheres for superior sodium-ion storage.

论文作者：Fanyan Zeng,Baoquan Liu,Yang Pan,Shile Chu,Guo Cheng,Tao Lu,Zhi Chen,Zhaohui Hou.