Aligning graphene sheets in PDMS for improving output performance of triboelectric nanogenerator

- Aligned graphene sheets in PDMS film (AGS@PDMS) is fabricated by spin-coating technique.
- Influence of morphology and alignment of filling carbon materials in PDMS have been compared.
- The AGS@PDMS film has larger energy storage ability and lower dielectric loss.
- Voltage applied on the TENG is distributed to micro capacitors formed by AGSs.

In this paper, aligned graphene sheets (AGS) embedded in PDMS (AGS@PDMS) has been prepared by repeated spin-coating (SC) technique. The triboelectric nanogenerator (TENG) based on the AGS@PDMS film is fabricated and its electric output is investigated systematically with different contents of filling graphene sheets and different spin-coating layers. The PDMS embedded with AGS is compared with that of disordered graphene sheets and graphite particles with different sizes. The capacitance, dielectric loss, conductivity and resistance of the PDMS composite film are characterized and analyzed. The output current of the TENG based on AGS@PDMS film is 3 times as much as that of the TENG based on pure PDMS film and the output power density reaches 4.8 W/m2 at the load resistance of 15 MΩ. In addition, the TENG can be used as a pressure sensor to measure the mass and height of an object. This work demonstrates that the voltage applied on whole TENG is distributed to micro capacitors formed by aligned graphene sheets in PDMS, by which the higher breakdown voltage and energy conversion ability are achieved.

The TENG based on aligned graphene sheets embedded in PDMS has been fabricated by repeated spin-coating technique, which has the higher breakdown voltage and lower dielectric loss owning to the oriented distribution of graphene sheets and excellent output performance.234