Synthesis of biowaste-derived carbon-dot-mediated silver nanoparticles and the evaluation of electrochemical properties for supercapacitor electrodes

• Navya Kumari Tenkayala,
• Chandan Kumar Maity,
• Md Moniruzzaman and
• Subramani Devaraju

Beilstein J. Nanotechnol. 2025, 16, 933–943, doi:10.3762/bjnano.16.71

• as-synthesized PG-CDs-AgNPs electrode exhibited the maximum specific capacitance of 540 F/g in a three-electrode study. The asymmetric supercapacitor (ASC) device with PG-CDs-AgNPs as the positive electrode reached the maximum specific capacitance of 200 F/g having a superior energy density of 71 W·h

• electrodes for energy storing. Keywords: asymmetric supercapacitor; carbon dots; fluorescence emission; green approach; silver nanoparticles; Introduction The extensive usage of fossil fuels is a result from the rising demand for energy. However, the use of fossil fuels is not sufficient to attend the

• discharge time. Electrochemical analysis of the asymmetric supercapacitor device in a 1 M TEABF4/DMSO organic electrolyte Electrochemical evaluations attributed that in the three-electrode configuration, the PG-CDs-AgNPs electrode possessed superior electrochemical activity. Thus, utilizing carbon black (CB

High-performance asymmetric supercapacitor made of NiMoO₄ nanorods@Co₃O₄ on a cellulose-based carbon aerogel

• Meixia Wang,
• Jing Zhang,
• Xibin Yi,
• Benxue Liu,
• Xinfu Zhao and
• Xiaochan Liu

Beilstein J. Nanotechnol. 2020, 11, 240–251, doi:10.3762/bjnano.11.18

• porous structure, the NiMoO4@Co3O4/CA ternary composite yields electrodes with an enhanced specific capacitance of 436.9 C/g at a current density of 0.5 A/g and an excellent rate capability of 70.7% capacitance retention at 5.0 A/g. Moreover, an advanced asymmetric supercapacitor (ASC) is assembled using

• on the above considerations, we present a simple scalable strategy to fabricate an integrated NiMoO4@Co3O4 hierarchical porous structure aligned on CA, which is derived from a cellulose precursor, to be applied in an advanced asymmetric supercapacitor (ASC). The NiMoO4 nanorods originated from ZIF-67

Ultrathin Ni_1−xCo_xS₂ nanoflakes as high energy density electrode materials for asymmetric supercapacitors

• Xiaoxiang Wang,
• Teng Wang,
• Rusen Zhou,
• Lijuan Fan,
• Shengli Zhang,
• Feng Yu,
• Tuquabo Tesfamichael,
• Liwei Su and
• Hongxia Wang

Beilstein J. Nanotechnol. 2019, 10, 2207–2216, doi:10.3762/bjnano.10.213

• exhibited a maximum specific capacity of 1066.8 F·g−1 (533.4 C·g−1) at 0.5 A·g−1 and a capacity retention of 63.4% at 20 A·g−1 in an asymmetric supercapacitor (ASC). The ASC showed a superior energy density of 100.5 Wh·kg−1 (at a power density of 1.5 kW·kg−1), an ultrahigh power density of 30 kW·kg−1 (at an

• evaluate energy density and power density of the Ni1−xCoxS2 material for practical applications, the as-prepared Ni1−xCoxS2/NF as a positive electrode and the commercial YP-50F activated carbon (AC/NF) as a negative electrode (Figure 4a) were assembled to an asymmetric supercapacitor. As shown in

• usable potential windows were found up to 1.6 V. Polarization occurred when the potential was expanded beyond this value (1.7–1.8 V). The as-fabricated asymmetric supercapacitor showed battery behaviour in the range of 0–1.6 V at different scan rates as shown in Figure 4c. The capacity of the device has

Facile synthesis of carbon nanotube-supported NiO//Fe₂O₃ for all-solid-state supercapacitors

• Shengming Zhang,
• Xuhui Wang,
• Yan Li,
• Xuemei Mu,
• Yaxiong Zhang,
• Jingwei Du,
• Guo Liu,
• Xiaohui Hua,
• Yingzhuo Sheng,
• Erqing Xie and
• Zhenxing Zhang

Beilstein J. Nanotechnol. 2019, 10, 1923–1932, doi:10.3762/bjnano.10.188

• mAh·g−1 at 2 A·g−1 with a capacitance retention of 40% at 40 A·g−1. The obtained CC-CNT@NiO cathode exhibits a high capacity of 527 mAh·g−1 at 2 A·g−1 and an excellent rate capability with a capacitance retention of 78% even at 40 A·g−1. The all-solid-state asymmetric supercapacitor fabricated with

• cathode were prepared. CNTs significantly improved the conductivity and enhanced the capacity of Fe2O3 up to 226 mAh·g−1 at 2 A·g−1, and capacity of NiO to 527 mAh·g−1 at 2 A·g−1. Furthermore, by assembling the two electrodes, an asymmetric supercapacitor (ASC) with a high energy density of 63.3 Wh·kg−1

• Discussion Figure 1 shows the process of synthesizing cathode and anode, and finally, the asymmetric supercapacitor. The details can be seen in the Experimental section. Anode material CC-CNT@Fe2O3 CNTs were grown on CC by chemical vapour deposition (CVD). As shown in Figure 2a, CNTs grow homogeneously with

A Ni(OH)₂ nanopetals network for high-performance supercapacitors synthesized by immersing Ni nanofoam in water

• Donghui Zheng,
• Man Li,
• Yongyan Li,
• Chunling Qin,
• Yichao Wang and
• Zhifeng Wang

Beilstein J. Nanotechnol. 2019, 10, 281–293, doi:10.3762/bjnano.10.27

• energy density is approximately three times larger than that of a thin-film lithium ion battery (1–12 mW h/cm3, 4 V/500 μAh) [52] and far exceeds that of a MnO2-Ni(OH)2/AB//active carbon asymmetric supercapacitor (3.62 mWh/cm3 at 11 mW/cm3) [39] and a NiCo-LDH//AC asymmetric capacitor (7.4 mWh/cm3 at 103