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NiMoO4 nanorods (NRs) were successfully fabricated on Ni foam with robust adhesion via a simple and cost-effective hydrothermal treatment, followed by a calcined process. In a three-electrode configuration with 3 mol L−1 KOH aqueous solution. The NiMoO4 NRs supported on Ni foam as working electrodes achieve a high specific capacity of 1320 C g−1 at a charge and discharge current density of 2 mA cm−2, and a desirable rate capability (884 C g−1 even at 10 mA cm−2) and a superior cycling ability with 88% capacity retention after 4000 cycles at 10 mA cm−2. To enhance the energy density and enlarge the voltage window, the aqueous hybrid supercapacitor has subsequently been constructed by employing the NiMoO4 and activated carbon electrodes as positive and negative electrodes, respectively, which delivered a high energy density of 52 Wh kg−1 at a power density of 725 W kg−1. Impressively, the device indicates a long-term cycling stability with capacitance retention of 123% even after 9000 cycles in aa safe voltage range from 0 V to 1.45 V. These results definitely imply the promising prospect of NiMoO4 NR electrodes for application in supercapacitors.

Due to their highly porous structures, metal organic framework materials are widely used in analytic areas. In this paper, Cr-metal organic framework (MIL-101(Cr)) modified electrode was prepared and then was used as electrochemical sensor for the detection of bisphenol A (BPA). By using one kind of surfactant of cetyltrimethylammonium bromide (CTAB), the analytic performances of MIL-101 (Cr) towards BPA detection were greatly improved. Compared with pure MIL-101 (Cr), the differential pulse voltammetry (DPV) behavior of CTAB/MIL-101 (Cr) was improved 3.0 times in the presence of BPA. The hydrophobic long chain alkanes of CTAB can improve the enrichment and electrochemical oxidation for BPA. The CTAB/MIL-101 (Cr) sensor exhibited a linear range from 20 to 350 nM and a low detection limit of 9.95 nM (LOD = 3sb/S) and showed good reproducibility, stability and selectivity. Finally, real samples of dusts from E-waste recycling area in South China were collected and the CTAB/MIL-101 (Cr) sensor demonstrated satisfactory results for BPA detection from these dust samples.

A new photo-electrochemical sensor based on MIL-101(Cr) MOF/carbon black (CB) is fabricated and characterized. By using differential pulse voltammetry, dopamine (DA) can be effectively detected using a photo-electrochemical MIL-101(Cr)/CB sensor under visible light. The CB acts as the electron bridge to combine with the large specific surface area and photo-catalytic feature of MOF, which contribute to the improvements of sensitivity of DA detection. The concentration of the catalyst, pH value, accumulation potential, and accumulation time were also optimized. Furthermore, the electrochemical performances of MIL-101(Cr)/CB sensor was investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scan rate, electrochemically active surface area (ECSA), and amperometric responses. A detection limit of 0.38 nM (LOD = 3 sb/S, sb = 0.028) and a working range of 1 nM to 2.22 μM has been achieved. The MIL-101(Cr)/CB sensor exhibits excellent reproducibility, stability, and selectivity and also has satisfactory recovery rate for the analysis of real samples including calf serum and human urine.

In this paper, the detection performances of carbon black (CB) for bisphenol A (BPA) can be greatly improved by using a surfactant of cetyltrimethylammonium bromide (CTAB). The cyclic voltammetry (CV) behavior of CTAB/CB for BPA can be improved 6 times, compared with CB. The hydrophobicity of the CTAB long-chain alkyl end can enhance the enrichment ability of BPA. Meanwhile, CB can act as an electron transmission bridge to accelerate the electrons transfer to external circuit, thereby improving the sensing signal of CTAB/CB sensor for BPA. The sensor displays a linear range of 0.04 to 0.99 μM, a low detection limit of 0.013 μM and has good reproducibility and selectivity. Finally, the sensor can also be successfully used for detecting BPA in actual samples including tap water and human urine.