Jhonatam Pinheiro Mendonça, Raíssa Soares Penha, Scarllett Lalesca Lima, Sonia Letichevsky, Liying Liu, Carlos Castro, Marco Aurélio Suller Garcia
In this study, sulfur-modified MnO2 nanowires (MnO2-S) were synthesized via a two-step hydrothermal and solid-state process and evaluated as battery-type electrodes for hybrid supercapacitors. Transmission electron microscopy (TEM) and high-resolution TEM confirmed morphological integrity, while structural changes induced by sulfur inclusion were observed at the atomic scale, suggesting surface reconstruction and altered interplanar spacing. Electrochemical studies demonstrated that the 70% MnO2-S electrode achieved a high specific capacitance of 807.5 F g−1 at 1 A g−1 and retained 52.6% of its capacitance at 10 A g−1. The hybrid supercapacitor assembled with 70% MnO2-S as the cathode and activated carbon as the anode displayed a mixed pseudocapacitive/electric double-layer capacitance behavior, delivering an energy density of 35.81 Wh k g−1 and a power density of 934.17 W kg−1. Notably, the device showed good cycling stability up to 8000 cycles. Here, we managed to demonstrate how controlled sulfur incorporation simultaneously modulates the MnO2 lattice, enhances ion/electron transport through defect-assisted pathways, and stabilizes long-term electrochemical performance, revealing a tunable structure–property relationship that has not been previously established for MnO2-S heterostructures. Thus, the synergistic effects between sulfur and MnO2 nanostructures support their application as high-capacity electrodes for next-generation supercapatteries, combining Faradaic energy storage with fast charge–discharge kinetics.
本研究采用水热法和固态法两步合成了硫修饰二氧化锰纳米线(MnO2- s),并对其作为混合超级电容器的电池型电极进行了评价。透射电子显微镜(TEM)和高分辨率透射电子显微镜(TEM)证实了形貌的完整性,而在原子尺度上观察到硫包裹体引起的结构变化,表明表面重构和面间距的改变。电化学研究表明,70% MnO2-S电极在1 a g−1条件下具有807.5 F g−1的高比电容,在10 a g−1条件下保持了52.6%的比电容。以70% MnO2-S为阴极,活性炭为阳极组装的混合超级电容器表现出混合的赝电容/电双层电容行为,能量密度为35.81 Wh kg−1,功率密度为934.17 W kg−1。值得注意的是,该设备显示出良好的循环稳定性,高达8000次循环。在这里,我们成功地展示了控制硫的掺入如何同时调节MnO2晶格,通过缺陷辅助途径增强离子/电子传输,并稳定长期电化学性能,揭示了一种可调节的结构-性质关系,这是以前没有建立的MnO2- s异质结构。因此,硫和二氧化锰纳米结构之间的协同效应支持它们作为下一代超级电容器的高容量电极的应用,将法拉第能量存储与快速充放电动力学相结合。
{"title":"Sulfur-Induced Lattice Modulation and Charge-Transport Enhancement in MnO2 Nanowires for Hybrid Energy Storage","authors":"Jhonatam Pinheiro Mendonça, Raíssa Soares Penha, Scarllett Lalesca Lima, Sonia Letichevsky, Liying Liu, Carlos Castro, Marco Aurélio Suller Garcia","doi":"10.1002/est2.70336","DOIUrl":"https://doi.org/10.1002/est2.70336","url":null,"abstract":"<p>In this study, sulfur-modified MnO<sub>2</sub> nanowires (MnO<sub>2</sub>-S) were synthesized via a two-step hydrothermal and solid-state process and evaluated as battery-type electrodes for hybrid supercapacitors. Transmission electron microscopy (TEM) and high-resolution TEM confirmed morphological integrity, while structural changes induced by sulfur inclusion were observed at the atomic scale, suggesting surface reconstruction and altered interplanar spacing. Electrochemical studies demonstrated that the 70% MnO<sub>2</sub>-S electrode achieved a high specific capacitance of 807.5 F g<sup>−1</sup> at 1 A g<sup>−1</sup> and retained 52.6% of its capacitance at 10 A g<sup>−1</sup>. The hybrid supercapacitor assembled with 70% MnO<sub>2</sub>-S as the cathode and activated carbon as the anode displayed a mixed pseudocapacitive/electric double-layer capacitance behavior, delivering an energy density of 35.81 Wh k g<sup>−1</sup> and a power density of 934.17 W kg<sup>−1</sup>. Notably, the device showed good cycling stability up to 8000 cycles. Here, we managed to demonstrate how controlled sulfur incorporation simultaneously modulates the MnO<sub>2</sub> lattice, enhances ion/electron transport through defect-assisted pathways, and stabilizes long-term electrochemical performance, revealing a tunable structure–property relationship that has not been previously established for MnO<sub>2</sub>-S heterostructures. Thus, the synergistic effects between sulfur and MnO<sub>2</sub> nanostructures support their application as high-capacity electrodes for next-generation supercapatteries, combining Faradaic energy storage with fast charge–discharge kinetics.</p>","PeriodicalId":11765,"journal":{"name":"Energy Storage","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/est2.70336","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145983447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}