Journal of Nanomedicine & Nanotechnology

Enhanced piezoelectric and electrocatalytic performance of 2D layered materials using a first-principles approach

26^th International Conference on ADVANCED NANOSCIENCE AND NANOTECHNOLOGY

December 05-06, 2022 | Dubai, UAE

Parrydeep Kaur Sachdeva, Shuchi Gupta and Chandan Bera

Institute of Nano Science and Technology, India
Panjab University, India

Posters & Accepted Abstracts: J Nanomed Nanotechnol

Abstract:

Two-dimensional (2D) graphene, monochalcogenides and transition metal dichalcogenides (TMDCs) have diversified applications in piezotronics, electrocatalysis and energy harvesting. The group-VI Tellurene monolayer exhibits robust mechanical properties and giant piezoelectricity in its two phases. The properties are highly tunable by the applied biaxial and uniaxial strains such that the predicted values are remarkably higher, that is 23 and 12 times the piezoelectric coefficient of MoS2 monolayer with biaxial and uniaxial strain in the zigzag direction, respectively. The origin of huge piezoelectricity is attributed to the relatively large Born effective charges (BECs) of Te atoms. An inplane negative Poisson's ratio of -0.024 is obtained under positive tensile strain in the zigzag direction of the β’-Te monolayer. The negative Poisson’s ratio (NPR) behavior is due to the puckered structure of Te having a chairlike arrangement. Recently, TMDCs have become the area of focus to get cost effective and efficient electrocatalysts. In 2D, greater exposed surface area results in more active sites to support the electrocatalytic reactions but have high OER/HER overpotentials. Therefore, to improve the overall catalytic activity, doped graphene and molybdenum dichalcogenide heterostructures are evaluated using density functional theory. The Janus MoSSe and P-doped graphene heterostructure is found to have OER overpotential smaller by ~40% and ~13% as compared to MoS2 and MoSe2 heterostructures. The calculated HER overpotential is comparable to the value of benchmark HER catalyst, Pt. Also, the overpotential values are smaller than the parent monolayers graphene and MoS2. These exotic properties make them promising candidates for applications in energy harvesting.