2025/07/19 by Gunhee Park, Dong Won Jeon, Il-Seop Jang +8 · 1 voice
Engineering · Environmental Science · #Advanced Battery Materials and Technologies #Advancements in Battery Materials #Chemical Synthesis and Characterization
paper · pdf · doi:10.26599/jac.2025.9221138
openalex publication_date 2025/07/19 · openalex created_date 2025/07/20 · openalex updated_date 2026/07/18
The development of electrolytes with high ionic conductivity and stable electrode-electrolyte interfaces is crucial for the practical realization of solid-state sodium batteries. In this study, the effect of heteroatom doping in von-Alpen-type NASICON was investigated by substituting Zr<sup>4+</sup> with Mg<sup>2+</sup>, Zn<sup>2+</sup>, and La<sup>3+</sup> to enhance its material properties and evaluate its potential for solid-state sodium battery applications. Computational chemistry was employed to predict the thermodynamic stability influenced by dopant introduction and the changes in ionic conductivity arising from crystal structure distortion, with the predictions validated by experiments. The optimized Zn<sup>2+</sup>-doped NASICON (Zn-NZSP0.07) exhibited the highest total ionic conductivity of 2.74 × 10<sup>−</sup><sup>3</sup> S cm<sup>−</sup><sup>1</sup>, representing a 4.5-fold increase compared to undoped NASICON (6.00 × 10<sup>−</sup><sup>4</sup> S cm<sup>−</sup><sup>1</sup>). The material also showed a high relative density of 99.1%, indicating a compact and well-sintered microstructure, as confirmed by a three-point bending test. It further achieved a high critical current density of 1.4 mA cm<sup>−</sup><sup>2</sup> in symmetric cell testing. Additionally, a Na<sub>3</sub>V<sub>2</sub>(PO<sub>4</sub>)<sub>3</sub> || Zn-NZSP0.07 || Na cell delivered an initial capacity of 103.9 mAh g<sup>−</sup><sup>1</sup> at 0.1 A g<sup>−</sup><sup>1</sup> and retained 73.4% of its capacity after 200 cycles. These results demonstrate that optimal heteroatom doping is crucial for enhancing the performance of NASICON.