Simultaneous modification of dual-substitution with CeO2 coating boosting high performance sodium ion batteries

Que Huang; Chenghao Qian; Changcheng Liu; Yanjun Chen

doi:10.1016/j.jcis.2023.10.075

Simultaneous modification of dual-substitution with CeO₂ coating boosting high performance sodium ion batteries

J Colloid Interface Sci. 2024 Jan 15;654(Pt A):626-638. doi: 10.1016/j.jcis.2023.10.075. Epub 2023 Oct 17.

Authors

Que Huang¹, Chenghao Qian², Changcheng Liu³, Yanjun Chen⁴

Affiliations

¹ School of Environment and Safety Engineering, North University of China, Taiyuan 030051, Shanxi, People's Republic of China; Institute of Advanced Energy Materials and Systems, North University of China, Taiyuan 030051, Shanxi, People's Republic of China; School of Resources and Safety Engineering, Central South University, Changsha 410010, Hunan, People's Republic of China.
² School of Environment and Safety Engineering, North University of China, Taiyuan 030051, Shanxi, People's Republic of China; Institute of Advanced Energy Materials and Systems, North University of China, Taiyuan 030051, Shanxi, People's Republic of China. Electronic address: sz202214078@st.nuc.edu.cn.
³ School of Environment and Safety Engineering, North University of China, Taiyuan 030051, Shanxi, People's Republic of China; Institute of Advanced Energy Materials and Systems, North University of China, Taiyuan 030051, Shanxi, People's Republic of China. Electronic address: ccliu@nuc.edu.cn.
⁴ Institute of Advanced Energy Materials and Systems, North University of China, Taiyuan 030051, Shanxi, People's Republic of China; School of Materials Science and Engineering, North University of China, Taiyuan 030051, Shanxi, People's Republic of China. Electronic address: yjchen@nuc.edu.cn.

PMID: 37864868
DOI: 10.1016/j.jcis.2023.10.075

Abstract

Na₃V₂(PO₄)₃ (NVP) is highly valued based on the stable construction among the polyanionic compounds. Nevertheless, the drawback of low intrinsic conductivity has been impeded its further application. In this paper, the internal channels of the crystal structure are extended by the introduction of larger radius Ce³⁺, which increases the transport rate of Na⁺. The introduction of Mo⁶⁺ replacing the V site leads to a beneficial n-type doping effect and facilitates the transportation of electrons. Besides, CeO₂ cladding is introduced to further enhance the electronic conductivity of NVP system. Initially, CeO₂ serves as an n-type semiconductor and functions as a conductive additive to significantly enhance the electronic conductivity of the electrode, thereby improving the electrochemical characteristics. Moreover, CeO₂ functions as an oxygen buffer, aiding in the maintenance of active metal dispersion during operation and enabling efficient electron transfer between CeO₂ and [VO₆] octahedra in NVP, thus fostering outstanding electrical connectivity between the oxides. CeO₂ cladding can be effectively integrated with the carbon layer to stabilize the NVP system. Comprehensively, the modified Na₃V_1.79Ce_0.07Mo_0.07(PO₄)₃/C@8wt.%CeO₂ (CeMo0.07@8wt.%CeO₂) composite exhibits excellent rate and cycling properties. It delivers a capacity of 113.4 mAh/g at 1C with a capacity retention rate of 80.3 % after 150 cycles. Even at 10C and 40C, it also submits high capacities of 84.7 mAh/g and 76 mAh/g, respectively. Furthermore, the CHC//CeMo0.07@8wt.%CeO₂ asymmetric full cell possesses excellent sodium storage property, indicating its prospective application potentials.

Keywords: CeO(2) cladding; Electronic conductivity; N-type; Na(3)V(2)(PO(4))(3); Sodium ion battery.