Li Zhiheng, Xu Junming, Ding Xinqi, Zhu Haoran, Wu Jianfeng
College of Electronic Information, Hangzhou Dianzi University, Hangzhou 310018, China.
College of Information Science & Technology, Zhejiang Shuren University, Hangzhou 310015, China.
Nanomaterials (Basel). 2025 Apr 23;15(9):643. doi: 10.3390/nano15090643.
Metal-organic frameworks (MOFs) are regarded as advanced supercapacitor materials owing to their high surface area, redox-active sites, and porosity. However, their insufficient charge carrier mobility remains a critical limitation for practical application. Integrating MOFs with conductive carbon substrates is an effective strategy to break through this limitation. However, conventional carbon materials often require complex preparation methods and pre-activation steps for use in MOF composites. Herein, multilayer graphene (MLG) mechanically exfoliated from expandable graphite is employed as a substrate, and a van der Waals force-assisted chemical deposition method is developed to directly anchor Ni-MOF onto its surface without requiring pre-activation treatment. To optimize the composite, Ni-MOFs with various mass loadings are synthesized on MLG surface. The morphological characteristics and energy storage performance of these composites are thoroughly characterized. Ni-MOF/MLG-0.30 (with a 70.8% Ni-MOF loading on MLG) features a porous stacking structure of well-crystalline Ni-MOF parallelogram nanosheets on MLG, exhibiting optimal electrochemical performance. The composite achieves 1071.4 F·g at 1 A·g, and a capacitance retention of 64.9% at the elevated current density of 10 A·g. Meanwhile, the composite maintains 63.2% of its initial capacitance after 5000 charge/discharge cycles at 4 A·g. A hybrid supercapacitor is fabricated using Ni-MOF/MLG-0.30 cathode and activated carbon anode, delivering 27.9 Wh·kg energy density at 102.5 W·kg power output.
金属有机框架材料（MOFs）因其高比表面积、氧化还原活性位点和孔隙率而被视为先进的超级电容器材料。然而，其电荷载流子迁移率不足仍然是实际应用中的一个关键限制。将MOFs与导电碳基底集成是突破这一限制的有效策略。然而，传统的碳材料在用于MOF复合材料时通常需要复杂的制备方法和预活化步骤。在此，采用从可膨胀石墨机械剥离的多层石墨烯（MLG）作为基底，并开发了一种范德华力辅助化学沉积方法，无需预活化处理即可将Ni-MOF直接锚定在其表面。为了优化复合材料，在MLG表面合成了不同质量负载的Ni-MOF。对这些复合材料的形态特征和储能性能进行了全面表征。Ni-MOF/MLG-0.30（MLG上Ni-MOF负载量为70.8%）在MLG上具有结晶良好的Ni-MOF平行四边形纳米片的多孔堆叠结构，表现出最佳的电化学性能。该复合材料在1 A·g时的比电容为1071.4 F·g，在10 A·g的高电流密度下电容保持率为64.9%。同时，该复合材料在4 A·g下经过5000次充放电循环后仍保持其初始电容的63.2%。使用Ni-MOF/MLG-0.30阴极和活性炭阳极制备了一种混合超级电容器，在102.5 W·kg的功率输出下，能量密度为27.9 Wh·kg。
