Accelerated Ionic and Charge Transfer through Atomic Interfacial Electric Fields for Superior Sodium Storage
Accelerated Ionic and Charge Transfer through Atomic Interfacial Electric Fields for Superior Sodium Storage
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原子界面电场加速离子和电荷转移用于优质钠的储存
DOI：
10.1021/acsnano.2c00089
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发表时间：
2022-03-22
期刊：
影响因子：
17.1
通讯作者：
Yan, Chenglin
中科院分区：
文献类型：
--
作者：
Lu, Xueyi;Shi, Yuansheng;Yan, Chenglin
原子界面电场具有促进离子和电荷转移以及加速电化学反应动力学的巨大潜力。这里，异质结构内的内置电场是通过单层钛酸盐/石墨烯（还原的氧化石墨烯）纳米片作为构建块的静电组装产生的。扫描开尔文探针显微镜通过检测异质结构中不同纳米片的不平衡表面电势来确认内置电场的存在，这有助于离子和电子转移，从而在0.05 A g（-1）下实现245 mAh g（-1）的优异可逆钠存储容量。理论分析也证实了电场可以提高电导率，促进电子在原子界面的转移。此外，原位TEM观察证实了钠离子的均匀嵌入和非常小的体积膨胀的杂化材料。结果，实现了3000次循环的高稳定寿命，容量保持率为98.8%。这项工作证明了通过原子界面电场加速离子和电荷转移对于上级钠存储的重要性。
Atomic interfacial electric fields hold great potential for boosting ionic and charge transfer and accelerating electrochemical reaction kinetics. Here, built-in electric fields within the heterostructure are created by electrostatic assembly of unilamellar titano-niobate/graphene (reduced graphene oxide) nanosheets as building blocks. Scanning Kelvin probe microscopy confirms the existence of built-in electric fields by detecting the unbalanced surface potential of disparate nanosheets in the heterostructure, which facilitates ion and electron transfer, thus enabling an excellent reversible sodium storage capacity of 245 mAh g(-1) at 0.05 A g(-1). Theoretical analysis also confirms that the electric field can enhance the electric conductivity and facilitate electron transfer at the atomic interface. Moreover, in situ TEM observations confirm the homogeneous intercalation of sodium ions and very small volume expansion of the hybrid materials. As a result, a highly stable lifetime of 3000 cycles is achieved with capacity retention of 98.8%. This work attests the importance of accelerating ionic and charge transfer through atomic interfacial electric field for superior sodium storage.