Interspersed Reticulate Cu2WS4 Nanocrystal-PVDF/Ni Triboelectric Nanogenerators for Rhodamine B Degradation

Decahedral Cu2WS4 nanocrystal grains with a three-layer body-centered tetragonal crystal phase were successfully prepared by a simple hydrothermal method. Then, the interspersed reticulate Cu2WS4 nanocrystal-poly(vinylidene difluoride) (PVDF)/Ni composites were prepared by filling the mixed sol of organic ferroelectric polyvinylidene difluoride (PVDF) and Cu2WS4 nanocrystal grains into the void of Ni foam. Subsequently, polytetrafluoroethylene (PTFE)/Cu was used as a negative triboelectric layer, the prepared interspersed reticulate Cu2WS4 nanocrystal-PVDF/Ni composites were used as the positive triboelectric layer, and then the interspersed reticulate triboelectric nanogenerators (TENGs) were assembled. The use of the interspersed reticulate Ni electrode in the TENGs effectively reduces the effective thickness of the triboelectric layer, and the incorporation of Cu2WS4 nanocrystal grains into ferroelectric PVDF increases the dielectric constant of the triboelectric layer by enhancing the space charge polarization. Obviously, a reduction of the effective thickness and an increase of the dielectric constant further enhance the output V-OC by nearly 20 times and the J(SC) of the Cu2WS4 nanocrystal-PVDF/Ni TENG by nearly 10 times, and TENG has good output stability. Lastly, the TENG was successfully used as the power supply to perform the electrocatalytic degradation of RhB, which exhibits high efficiency and excellent duration stability. The works provide good ideas and methods for the treatment of marine pollutants.