Functional Porous Graphene Membranes: From Superhydrophobic to Slippery

Abstract

A simple and efficient route to functionalize porous graphene is identified. The method enables the modification of porous graphene with varying surface properties ranging from lotus-like superhydrophobic surfaces to slippery surfaces. The method offers a route to superior membrane fabrication with versatile industrial applications. The findings clearly show the possibility of fabricating superhydrophobic surfaces with porous graphene as a base, which is relevant for oil-water separation and other membrane applications. The filament-like structures observed on the functionalized graphene mimic the properties of a lotus leaf. The measured water contact angle (WCA) of these modified surfaces reaches values as high as 160° with a contact angle hysteresis (CAH) below 10°, allowing for easy roll-off of water droplets. A Slippery behavior of the graphene surfaces is realized when the fibrillar structures on the graphene surfaces are infused with silicone oils. The work demonstrates the possibility of tuning the properties of graphene surfaces in a simple and efficient way and highlights possibly the first manufacturing method for graphene-based Slippery Liquid Infused Porous Surfaces (SLIPS).