Point Defect-Passivated MoS2 Nanosheet-Based High Performance Piezoelectric Nanogenerator

The piezoelectric characteristics of two-dimensional materials are of great interest for high-performance piezoelectric potential applications. The CVD-based large-area monolayer MoS2 is essential for practical applications.... [ view full abstract ]

The piezoelectric characteristics of two-dimensional materials are of great interest for high-performance piezoelectric potential applications. The CVD-based large-area monolayer MoS₂ is essential for practical applications. However, the CVD-based MoS₂ has the intrinsic defect of sulfur vacancies during the growth process, and these defects play an important role in screening the piezoelectric potential. So only small piezoelectric potential induced power output has been observed from the CVD-grown MoS₂. Here we demonstrate a high performance piezoelectric nanogenerator using CVD-based monolayer MoS₂ nanosheet by an additional sulfur treatment process during the MoS₂ growth process. The measured piezoelectric coefficient (d₁₁) of the CVD-grown large-area monolayer MoS₂ nanosheet is 3.73 pm V^-1 using lateral PFM methods, and it generates a peak power density of 0.8 mW, which is 10 times higher than that of the pristine monolalyer MoS₂ nanosheet.