Piezotronic effect of single/few-layers MoS2 nanosheets composite with TiO2 nanorod heterojunction

In this work, few-layers MoS2 nanosheets with highly exposed active edge sites on TiO2 nanorod (TNr) were successfully prepared by hydrothermal synthesis processes. The MoS2@TNr heterostructure possessed enhanced carrier concentration of 3.803 × 1015 cm−3 that was much higher than the bare TNr (1.714 × 108) as well as the pure MoS2 (7.662 × 1010) due to the synergistic effect of piezotronic performance. The piezoelectric catalytic degradation results showed that over 99% RhB and Cr (VI) was removed within 10 min under continuous stirring, and the catalytic reduction activity of Cr (VI) remained stable in the recycle experiments. The carriers were found to be effectively replenished by light illumination. Moreover, the nano-generator based on the MoS2@TNr/PDMS demonstrated good performance in harvesting mechanical energy. The unexceptionable piezoelectric performance of the MoS2@TNr heterojunctions was attributed to their unique morphology, i.e., few-layers MoS2 nanosheets grew along the surfaces of anatase TiO2 nanoparticles on TNr surface, forming the "edge-on" configuration.