High Performance Two Dimensional Few Layered Copper Doped MoS2 Nanosheets Based Flexible Piezoelectric Nanogenerator

Flexible piezoelectric nanogenerators based on two dimensional (2D) nanosheets are pivotal due to their ultrathin thickness, good mechanical strength and super flexibility with high efficiency. In present work, single crystalline copper (Cu) doped 2D MoS2 nanosheets was grown via low temperature hydrothermal technique. X-ray diffraction (XRD), High resolution- transmission electron microscope (HRTEM) confirmed the formation of the 2H phase of the Cu-doped MoS2 nanosheets with thickness and length in range of the 5-7 nm and 300-500 nm, respectively. Pristine and Cu-doped 2D MoS2 nanosheets based flexible nanogenerator were fabricated and piezoelectric output voltage was measured. Flexible Cu-doped MoS2 nanosheet: PDMS based flexible nanogenerator exhibited output voltage of 15 V even under low pressure, where as pristine MoS2 nanosheet based nanogenerator exbited low output voltage of 9 V under same force. Dielectric properties of pristine and Cu- doped MoS2 nanosheets were also investigated and high dielectric constant of about 6750 was obtained. The mechanism of enhanced output voltage was discussed in terms of the large polarisation and high dielectric constant from Cu-doped MoS2 nanosheets.