Desai Nakul, Sudhakar Y N, Selvakumar M, Devadiga Dheeraj
Department of Chemistry, Manipal Institute of Technology, Manipal Academy of Higher Education Manipal-576104 India
Manipal Technologies Limited Manipal 576104 Karnataka India.
RSC Adv. 2025 Aug 21;15(36):29613-29626. doi: 10.1039/d5ra04868k. eCollection 2025 Aug 18.
A hierarchical hybrid material (MnO@COP) with dual charge storage capabilities was created by synthesizing a triazine-based covalent organic polymer (COP) that is rich in nitrogen functionalities and integrating it with MnO nanoparticles. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), Brunauer-Emmett-Teller (BET) studies, and X-ray photoelectron spectroscopy (XPS) demonstrated a distinct architecture: MnO nanoparticles were uniformly embedded in a stable, porous COP matrix. MnO loading caused a modest decrease in surface area, but the composite still had the mesoporosity needed for quick ion diffusion. The existence of electroactive nitrogen centers-pyridinic, pyrrolic, and graphitic-and mixed-valence Mn/Mn species, which together improve redox kinetics and charge transfer routes, was verified by XPS analysis. An intriguing combination of electric double-layer capacitance (EDLC) and pseudocapacitive behavior was demonstrated by electrochemical experiments in a 1 M HSO electrolyte. The MnO@COP composite electrode in the three-electrode system had a high specific capacitance of 113 F g at 5 mV s and 69.1 F g at 0.1 A g, an energy density of 9.6 Wh kg and a power density of 500 W kg at 0.1 A g. The fabricated symmetric supercapacitor device maintained 95% of its capacitance after 10 000 charge-discharge cycles at 0.5 A g and provided a specific capacitance of 16.2 F g and energy density and power density of 2.25 Wh kg and 250 W kg at 0.2 A g, respectively. This study offers a viable method for combining the energy density of transition metal oxides with the quick kinetics of conductive organic networks, opening the door to long-lasting, highly effective energy storage devices.
通过合成富含氮官能团的基于三嗪的共价有机聚合物(COP)并将其与MnO纳米颗粒整合,制备了一种具有双电荷存储能力的分级混合材料(MnO@COP)。傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)、扫描电子显微镜(SEM)、能量色散X射线光谱(EDS)、布鲁诺尔-埃米特-泰勒(BET)研究和X射线光电子能谱(XPS)表明了一种独特的结构:MnO纳米颗粒均匀地嵌入在稳定的多孔COP基质中。MnO负载导致表面积略有下降,但复合材料仍具有快速离子扩散所需的介孔率。XPS分析证实了电活性氮中心(吡啶型、吡咯型和石墨型)以及混合价态的Mn/Mn物种的存在,它们共同改善了氧化还原动力学和电荷转移途径。在1 M HSO电解质中的电化学实验表明了双电层电容(EDLC)和赝电容行为的有趣组合。三电极系统中的MnO@COP复合电极在5 mV s时具有113 F g的高比电容,在0.1 A g时具有69.1 F g的比电容,在0.1 A g时能量密度为9.6 Wh kg,功率密度为500 W kg。制备的对称超级电容器装置在0.5 A g下进行10000次充放电循环后保持其电容的95%,在0.2 A g时提供16.2 F g的比电容,能量密度和功率密度分别为2.25 Wh kg和250 W kg。这项研究提供了一种将过渡金属氧化物的能量密度与导电有机网络的快速动力学相结合的可行方法,为持久、高效的储能装置打开了大门。