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Electric double layer capacitors (EDLCs) usually show high rate performance and long cycling spans but inferior specific capacitance, which are mainly created by restriction of the charge storage mechanism. To improve the capacitive performance, traditional methods include enlarging surface area, optimizing porous structures, and readjusting functional groups through heteroatom doping to electrode materials. Besides that, another promising approach is suggested, which is to enhance surface roughness of the electrode materials for ion storage and transport. To prove this view, two porous carbon materials were fabricated by activation-calcination methods, which allowed the materials to have identical surface area, porous structures, and surface composition but the surface roughness. Further electrochemical measurements exhibited that the optimal sample with higher roughness has remarkable specific capacitance (up to 562 F g -1 ), and the increment rate is more than 50% when compared with contrast sample (367 F g -1 ). Therefore, optimization of the surface roughness of electrode materials is another efficient route to make robust EDLCs.

Carbon electrode materials are fabricated from bean curd to replace costly Pt-based electrodes to degrade methyl red (MR) as self-driven by a multilayer linkage triboelectric nanogenerator (ML-TENG). With the sponge as the buffer layer and precharge injection, the peak open-circuit voltage, V oc , short-circuit current, I sc , and maximum power density of the ML-TENG can reach and remain stable at 1300 V, 1.2 mA, and 7.4 W m -2 (load resistance = 500 KΩ), respectively. Using the electric power generated by such an updated TENG, highly toxic and carcinogenic MR can be indirectly degraded to CO 2 through an oxidation process induced by active chlorine produced at the as-obtained carbon-based electrode interface. Such an electrochemical degradation mechanism is proposed based on the cyclic voltammogram, gas chromatograph-mass spectrometer, and mass spectrometer. With compelling features of the TENG and carbon materials, such as sustainable energy, high and stable output performance, cost savings, and high degradation efficiency, this work pioneers the marriage of the TENG with carbon-based materials to self-power electrochemical degradation of organic pollutants for environmental protection.

A rotary disc-structured triboelectric nanogenerator (rd-TENG) on the basis of free-standing electrification has been designed, where the aluminum composite panel has not been tailored to the stator becauseit is commercially available and cost-effective, has good electronic conductivity, and is easily processed. With the rotating speed increasing from 200 to 1000 rpm, the short-circuit current (I sc ) is sharply enhanced from 50 μA to 200 μA, while the measured open-circuit voltage (V oc ) and transferred charge (Q tr ) almost keep constant, 600 V and 0.4 μC, respectively. The matched load for the rd-TENG at a rotating speed of 600 rpm is 2.7 MΩ, generating a maximum power of 19.75 mW, which corresponds to a maximum power density of 2.28 W m -2 . Using the electric power generated by such a rd-TENG, highly toxic and carcinogenic 4-aminoazobenzene can be selectively treated to produce CO 2 or an oligomer via reasonably controlling electrochemical oxidation potentials. The underlying mechanism is tentatively proposed based on the cyclic voltammogram, gas chromatograph-mass spectrometer, electrochemical impedance spectroscopy, and UV-vis spectra. Here the electrochemical degradation in a single-compartment cell is more valid, preferable, and feasible. The output V oc and rectified current of rd-TENG guarantee its extensive application to self-power electrochemical degradation of other azo compounds, i.e., 2-(4-dimethylaminophenylazo) benzoic acid, to CO 2 . This work suggests that rd-TENG, sustainable energy, can be feasibly designed to self-power a practical electrochemical treatment of dyeing wastewater by harvesting vibration energy.

A cross-linked triboelectric nanogenerator with high performance is designed for the first time, which harvests vibrational energy to self-power the electrochemical oxidation of organic molecules. This system lays the groundwork for applications to an environmentally friendly production of important organic molecules and the waste treatment of organic pollutants., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An efficient soft-template method is proposed for the synthesis of peanut shell-like porous carbon as high-performance supercapacitor electrode materials. The procedure is based on the pyrolysis and chemical activation processes using N-phenylethanolamine as precursor and KOH as activation agent. In a three-electrode system, the resultant carbon material has a specific capacitance of 356 F g(-1) at 1 A g(-1) and a good stability over 1000 cycles. Besides, at a high current density of 30 A g(-1), it has a specific capacitance of 249 F g(-1) and maintains 96% after 10,000 cycles. In two-electrode cell configuration, it delivers about 21.53 Wh kg(-1) at a current density of 20 A g(-1), which is about 7 times higher than the commercial device (<3 Wh kg(-1)). Both high specific capacitance and excellent cycling stabilities guarantee its utilization in supercapacitors.