During the last years diverse Pillar [n]arenes have been intensively used as molecular systems for recognition and synthons for self-assembly, toward the construction of highly selective supramolecular materials or functional devices. They present an electron-rich cavity, as well as reactive rims that can be decorated with specific functional groups, resulting in the formation of tubular pillar shape architectures. For this reasons pillar[n]arenes are excellent candidates for the construction of artificial water, ionic, proton, or molecular channels through bilayer and polymeric membranes used for selective separations. This review integrate the most recent examples of pillar[n]arenes synthetic systems used to elaborate selective channels or nanodevices for selective water translocation, ion or proton rectification useful for important application in environmental sciences as water purification or medicine.