Xiao Junpeng, Yu Peng, Gao Hong, Yao Jing
Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, School of Physics and Electronic Engineering, Harbin Normal University, Harbin 150025, PR China; School of Physics and Electronic Engineering, Northeast Petroleum University, Daqing 163318, PR China.
Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, School of Physics and Electronic Engineering, Harbin Normal University, Harbin 150025, PR China.
J Colloid Interface Sci. 2023 Dec 15;652(Pt A):113-121. doi: 10.1016/j.jcis.2023.08.036. Epub 2023 Aug 7.
Schottky heterostructures have significant advantages for exciting charge transfer kinetics at material interfaces. In this work, endogenous NbCT/NbO Schottky heterostructures with a large active surface area were constructed using an in-situ architectural strategy. The semiconductor NbO has a low work function, and during the construction of NbCT/NbO Schottky heterostructures, there was an interfacial electron transfer, which resulted in a built-in electric field. The electrochemical reaction kinetics of NbCT/NbO Schottky heterostructures were enhanced due to the rapid transfer of charge driven by the electric field. The NbCT/NbO Schottky heterostructures have a large active surface area, which contributes to excellent electrolyte diffusion kinetics. Therefore, NbCT/NbO Schottky heterostructures have excellent lithium-ion storage capacity with 575 mAh/g after 200 cycles at 0.10 A/g, and 290 mAh/g after 1000 cycles at 2.00 A/g, without capacity fading. Furthermore, in-situ X-ray diffraction and ex-situ X-ray photoelectron spectroscopy analyses reveal the mechanisms for structure evolution and lithium-ion storage optimization of NbCT/NbO Schottky heterostructures during the electrochemical reaction. The construction of Schottky heterostructures with excited charge transport kinetics provides a novel idea for optimizing the lithium-ion storage activity of MXenes materials.
肖特基异质结构在激发材料界面电荷转移动力学方面具有显著优势。在本工作中，采用原位构筑策略构建了具有大活性表面积的内源性NbCT/NbO肖特基异质结构。半导体NbO具有低功函数，在NbCT/NbO肖特基异质结构的构建过程中，发生了界面电子转移，从而产生了内建电场。由于电场驱动电荷的快速转移，NbCT/NbO肖特基异质结构的电化学反应动力学得到增强。NbCT/NbO肖特基异质结构具有大活性表面积，这有助于实现优异的电解质扩散动力学。因此，NbCT/NbO肖特基异质结构具有优异的锂离子存储容量，在0.10 A/g下循环200次后为575 mAh/g，在2.00 A/g下循环1000次后为290 mAh/g，且无容量衰减。此外，原位X射线衍射和非原位X射线光电子能谱分析揭示了NbCT/NbO肖特基异质结构在电化学反应过程中的结构演变和锂离子存储优化机制。构建具有激发电荷传输动力学的肖特基异质结构为优化MXenes材料的锂离子存储活性提供了新思路。
