Goyal Megha, Pandey Sarvesh Kumar, Bhatnagar Nitu
Department of Chemistry, Manipal University Jaipur Jaipur-303007 Rajasthan India
Department of Chemistry, Maulana Azad National Institute of Technology Bhopal Bhopal-462003 Madhya Pradesh India
RSC Adv. 2025 Jul 16;15(31):25209-25220. doi: 10.1039/d5ra04329h. eCollection 2025 Jul 15.
To support various forms of energy storage systems for high power requirements, supercapacitors are essential as an additional type of energy storage device. In this study, magnesium oxide nanoparticles (MgONPs) were synthesized using a co-precipitation method and systematically evaluated as active electrode materials. FESEM images revealed a porous and aggregated surface morphology, which may facilitate ion transport by providing accessible diffusion pathways while Raman spectroscopy confirmed the presence of characteristic vibrational modes, including features associated with structural defects, which are commonly observed in nanostructured oxides. The electrochemical behavior of the MgONPs electrode material was evaluated using the three-electrode technique in a 2 M KOH aqueous electrolyte. At a current rate of 1 A g, a MgONPs electrode material exhibited a specific capacity of 11 F g. The CV behavior demonstrates the strong reversibility of the electrode material revealed a maximum specific capacitance of 99 F g at 10 mV s and good rate capability, underscoring the potential of MgONPs in energy storage devices. To complement the experimental observations, a density functional theory (DFT) study was conducted to examine the structural stability and electronic properties of MgONPs at the molecular level. The DFT-optimized geometry closely matched experimental lattice parameters, while a low HOMO-LUMO energy gap (Δ = -6.571 eV) indicated high reactivity and efficient charge transfer. Additional descriptors such as dipole moment, softness, and electrophilicity supported the electrochemical behavior observed experimentally. This integrated computational-experimental approach provides comprehensive insights into the fundamental properties of MgONPs, establishing them as promising, cost-effective, and high-performance electrode materials for next-generation supercapacitor systems.
为了支持用于高功率需求的各种形式的能量存储系统，超级电容器作为一种额外的能量存储设备至关重要。在本研究中，采用共沉淀法合成了氧化镁纳米颗粒（MgONPs），并将其作为活性电极材料进行了系统评估。场发射扫描电子显微镜（FESEM）图像显示出多孔且聚集的表面形态，这可能通过提供可及的扩散途径促进离子传输，而拉曼光谱证实了特征振动模式的存在，包括与结构缺陷相关的特征，这些在纳米结构氧化物中很常见。在2 M KOH水溶液电解质中使用三电极技术评估了MgONPs电极材料的电化学行为。在1 A g的电流速率下，MgONPs电极材料表现出11 F g的比容量。循环伏安（CV）行为表明电极材料具有很强的可逆性，在10 mV s时显示出99 F g的最大比电容和良好的倍率性能，突出了MgONPs在能量存储设备中的潜力。为了补充实验观察结果，进行了密度泛函理论（DFT）研究，以在分子水平上研究MgONPs的结构稳定性和电子性质。DFT优化的几何结构与实验晶格参数紧密匹配，而低的最高占据分子轨道-最低未占据分子轨道能隙（Δ = -6.571 eV）表明高反应活性和高效的电荷转移。诸如偶极矩、软度和亲电性等其他描述符支持了实验观察到的电化学行为。这种综合的计算-实验方法为MgONPs的基本性质提供了全面的见解，确立了它们作为下一代超级电容器系统有前景、经济高效且高性能的电极材料。
