jats:titleAbstract</jats:title> jats:pTwo-dimensional (2D) materials provide an intriguing means to not only study physical phenomena but also serve as disruptive membranes for ionic selectivity and sensing based applications. Atomic thinness of these materials affords a unique environment in an all-surface material to unlock challenges towards improving desalination, energy harvesting and DNA sensing. This review provides an overview on some common 2D materials used in membrane applications for solving these challenges along with opportunities where 2D materials could add value to existing solutions. Following this, different types of 2D materials and structures are discussed with their relative advantages and disadvantages highlighted. Fabrication and methods of creating pores within 2D membranes are then presented with a focus on altering surface characteristics. Selected works within the field are highlighted and placed into a wider context, comparing their merits and shortfalls. A discussion of state-of-the-art performance for ionic transport, molecular sensing and power generation is then presented. This review concludes with an outlook on emerging methods and discussing exciting future directions.</jats:p>