Prescriptive formulation of Inorganic Membranes on Aqueous Surface

Abstract Freestanding functional inorganic membranes have piqued immense interest, as they may extend the notion of a selective barrier beyond matter flow to encompass energy and even information flows, potentially unlocking new possibilities in advanced separation, catalysis, sensors, memories, optical filtering and ionic conductors. However, limited by the brittle nature of most inorganic materials along with their few surface unsaturated linkages, inorganic membranes are far less ubiquitous than their organic counterparts, which may be easily obtained from diverse top-down moldings and/or bottom-up syntheses. Up to now, only a few specific inorganic membranes were circuitously derived from the pre-deposited films by selective removal of the sacrificial substrates. Here, we demonstrate a facile strategy to switch the nucleation preference in the aqueous system, resulting in a versatile synthesis of various ultrathin inorganic membranes on solution surface. Through a comprehensive understanding of the kinematic evolution of floating building units for membrane construction, the phase diagram based on geometrical connectivity, as well as the principle of customizing membrane thickness and porosity, are established, providing access to unusual membrane topologies with complex architectures. This universal synthetic methodology, pivotal to both scientific and industrial communities, will hasten the exploitation of new functional membranes for a variety of novel applications.