Chen Yudan, Wang Pengbo, Truong Erica, Ogbolu Bright, Jin Yongkang, Oyekunle Ifeoluwa, Liu Haoyu, Islam M Mahinur, Poudel Tej, Huang Chen, Hung Ivan, Gan Zhehong, Hu Yan-Yan
Department of Chemistry and Biochemistry, Florida State University, Tallahassee, FL 32306, USA.
Materials Science and Engineering, Florida State University, Tallahassee, FL 32310, USA.
Angew Chem Int Ed Engl. 2024 Aug 26;63(35):e202408574. doi: 10.1002/anie.202408574. Epub 2024 Jul 22.
All-solid-state potassium batteries emerge as promising alternatives to lithium batteries, leveraging their high natural abundance and cost-effectiveness. Developing potassium solid electrolytes (SEs) with high room-temperature ionic conductivity is critical for realizing efficient potassium batteries. In this study, we present the synthesis of KSbSCl, showcasing a room-temperature ionic conductivity of 0.32 mS/cm and a low activation energy of 0.26 eV. This represents an increase of over two orders of magnitude compared to the parent compound KSbS, marking the highest reported ionic conductivity for non-oxide potassium SEs. Solid-state K magic-angle-spinning nuclear magnetic resonance on KSbSCl reveals an increased population of mobile K ions with fast dynamics. Ab initio molecular dynamics (AIMD) simulations further confirm a delocalized K density and significantly enhanced K diffusion. This work demonstrates diversification of the anion sublattice as an effective approach to enhance ion transport and highlights KSbSCl as a promising SE for all-solid-state potassium batteries.
全固态钾电池作为锂电池的有前景的替代方案而出现，这得益于钾的高天然丰度和成本效益。开发具有高室温离子电导率的钾固体电解质（SEs）对于实现高效钾电池至关重要。在本研究中，我们展示了KSbSCl的合成，其室温离子电导率为0.32 mS/cm，活化能低至0.26 eV。与母体化合物KSbS相比，这代表了超过两个数量级的提升，标志着非氧化物钾SEs报道的最高离子电导率。对KSbSCl进行的固态K魔角旋转核磁共振显示，具有快速动力学的可移动K离子数量增加。从头算分子动力学（AIMD）模拟进一步证实了K密度的离域化和K扩散的显著增强。这项工作证明了阴离子亚晶格的多样化是增强离子传输的有效方法，并突出了KSbSCl作为全固态钾电池有前景的SE。
