Apparent Softening of Wet Graphene Membranes on a Microfluidic Platform

作者：Ferrari Gustavo A; de Oliveira Alan B; Silvestre Lye; Matos Matheus J S; Batista Ronaldo J C; Fernandes Thales F D; Meireles Leonel M; Eliel Gomes S N; Chacham Helio; Neves Bernardo R A; Lacerda Rodrigo G

来源：ACS Nano, 2018, 12(5): 4312-4320.

DOI：10.1021/acsnano.7b08841

• graphene
• membranes
• microfluidic
• mechanical properties
• liquid interface

Graphene is regarded as the toughest two-dimensional material (highest in-plane elastic properties) and, as a consequence, it has been employed/proposed as an ultrathin membrane in a myriad of microfluidic devices. Yet, an experimental investigation of eventual variations on the apparent elastic properties of a suspended graphene membrane in contact with air or water is still missing. In this work, the mechanical response of suspended monolayer graphene membranes on a microfluidic platform is investigated via scanning probe microscopy experiments. A high elastic modulus is measured for the membrane when the platform is filled with air, as expected. However, a significant apparent softening of graphene is observed when water fills the microfluidic system. Through molecular dynamics simulations and a phenomenological model, we associate such softening to a water-induced uncrumpling process of the suspended graphene membrane. This result may bring substantial modifications on the design and operation of microfluidic devices which exploit pressure application on graphene membranes.

• 出版日期2018-5