Boichuk Andrii, Boichuk Tetiana, Kreĉmarová Marie, Eledath Changarath Mahesh, Abargues Rafael, Agouram Said, Sánchez-Royo Juan F
ICMUV, Instituto de Ciencia de Materiales, Universidad de Valencia, Valencia 46071, Spain.
King Danylo University, Ivano-Frankivsk 76000, Ukraine.
ACS Omega. 2025 Jun 25;10(26):28395-28403. doi: 10.1021/acsomega.5c03760. eCollection 2025 Jul 8.
In this study, we present a biphasic (orthorhombic/monoclinic) NaMnO material synthesized by using cheap and low-temperature sol-gel methods, which presents potential applications as an advanced cathode material for aqueous sodium-ion energy storage. By leveraging its unique structural and morphological properties, our approach optimizes the balance between diffusion-controlled and surface-controlled pseudocapacitive charge storage, significantly enhancing electrochemical performance with capacity values over 100 mAh/g. Electrochemical investigations reveal that the tailored morphology of NaMnO allows for a high pseudocapacitive contribution, with the NaSO electrolyte exhibiting the most stable cycling behavior and the highest capacity retention. Ex-situ X-ray diffraction, Raman spectroscopy, transmission electron microscopy, and X-ray photoemission techniques confirm both intercalation and surface pseudocapacitive reactions, highlighting the interplay between intercalation and adsorption processes. The calculated value of diffusion-controlled pseudocapacity contribution of about 55% enables superior charge storage capabilities and rapid charge/discharge rates. These findings establish biphasic NaMnO as a promising, structured, stable electrode material for next-generation, high-performance, and robust sodium energy storage systems.
在本研究中，我们展示了一种通过使用廉价且低温的溶胶-凝胶法合成的双相（正交晶系/单斜晶系）NaMnO材料，其作为水系钠离子储能的先进正极材料具有潜在应用。通过利用其独特的结构和形态特性，我们的方法优化了扩散控制和表面控制的赝电容电荷存储之间的平衡，以超过100 mAh/g的容量值显著提高了电化学性能。电化学研究表明，NaMnO的定制形态允许高赝电容贡献，其中NaSO电解质表现出最稳定的循环行为和最高的容量保持率。非原位X射线衍射、拉曼光谱、透射电子显微镜和X射线光电子能谱技术证实了嵌入和表面赝电容反应，突出了嵌入和吸附过程之间的相互作用。计算得出的扩散控制赝电容贡献值约为55%，实现了卓越的电荷存储能力和快速的充放电速率。这些发现确立了双相NaMnO作为下一代高性能、坚固的钠储能系统的一种有前景的、结构化的、稳定的电极材料。
