Membranes are recognized as a key component in many environment and energy‐related applications, but conventional membranes are challenged to satisfy the growing demand for ever more energy‐efficient ...processes. Janus membranes, a novel class with asymmetric properties on each side, have recently emerged and represent enticing opportunities to address this challenge. With an inner driving force arising from their asymmetric configuration, Janus membranes are appealing for enhancing energy efficiency in a variety of membrane processes by promoting the desired transport. Here, the fundamental principles to prepare Janus membranes with asymmetric surface wettability and charges are summarized, and how they work in conventional and unconventional membrane processes is demonstrated.
The rise of Janus membranes brings new opportunities to tackle challenges surrounding energy management, while also enabling novel functions that are not even viable when using conventional membranes.
Janus membranes are an emerging class of materials having opposing properties at an interface. This structure results in selective and often novel transport characteristics. In this Minireview, a ...definition of the Janus membrane, beyond merely asymmetric materials, is introduced and common fabrication strategies are outlined. Also presented are current and potential applications in directional transport, switchable permeation, and performance optimization with detailed mechanisms.
Crossing over: Janus membranes have received widespread interest over the past years. In this Minireview, a special definition of a Janus membrane is proposed and common fabrication methods of such membranes are outlined. Also summarized are the current and potential applications of Janus membranes in directional transport, switchable permeation, and performance optimization.
Over the past decades, polymer membranes are becoming more and more compelling due to their growing demand in environment, energy and health fields. Many efforts have been devoted to improve the ...membrane performance and extend their application via the methodology of surface engineering. One of the most promising strategies is mussel-inspired chemistry, which has become a powerful tool in membrane fabrication and modification because of its universality and versatility. Considering the increasing interest and advances in this field, we present this review regarding mussel-inspired chemistry in the surface engineering of polymer membranes. The adhesion mechanism and properties of polydopamine (as a representative) are briefly outlined at the beginning. Then detailed elaboration is followed on the applications of mussel-inspired chemistry in the surface science and technology of membranes. Catecholamines can be directly deposited on the membrane surface, act as an interface layer for post-modification, serve as a surface component of membrane and pre-decorate polymers for membrane modification or fabrication. Finally, we summarize recent research progress and give a further perspective of the mussel-inspired catecholamine in membrane science and technology.
Display omitted
•Critical review of mussel-inspired chemistry in membrane surface engineering.•Illustration of adhesion mechanisms and properties of polydopamine.•Outline of applications both in membrane fabrication and surface modification.•Great potentials in separation membranes with high-performance and multi-function.
Dopamine: Just the Right Medicine for Membranes Yang, Hao‐Cheng; Waldman, Ruben Z.; Wu, Ming‐Bang ...
Advanced functional materials,
February 21, 2018, Volume:
28, Issue:
8
Journal Article
Peer reviewed
Open access
Mussel‐inspired chemistry has attracted widespread interest in membrane science and technology. Demonstrating the rapid growth of this field over the past several years, substantial progress has been ...achieved in both mussel‐inspired chemistry and membrane surface engineering based on mussel‐inspired coatings. At this stage, it is valuable to summarize the most recent and distinctive developments, as well as to frame the challenges and opportunities remaining in this field. In this review, recent advances in rapid and controllable deposition of mussel‐inspired coatings, dopamine‐assisted codeposition technology, and photoinitiated grafting directly on mussel‐inspired coatings are presented. Some of these technologies have not yet been employed directly in membrane science. Beyond discussing advances in conventional membrane processes, emerging applications of mussel‐inspired coatings in membranes are discussed, including as a skin layer in nanofiltration, interlayer in metal‐organic framework based membranes, hydrophilic layer in Janus membranes, and protective layer in catalytic membranes. Finally, some critical unsolved challenges are raised in this field and some potential pathways are proposed to address them.
Mussel‐inspired polydopamine is a rising star in membrane science and technology. The most recent advances in polydopamine deposition are highlighted and summarized, as well as its emerging applications in nanofiltration, metal‐organic framework composite membranes, Janus membranes, and photocatalytic membranes.
Abstract
Solar‐driven evaporation process brings exciting opportunities to recover clean water and resources in a sustainable way from diverse sources like seawater and wastewater. Separation ...membranes, as a vital material in many environmental and energy applications, can contribute significantly to this process owing to their structural features. However, the unique roles of membranes in solar evaporator construction and process design are seldom recognized and not summarized yet from scientific principles and application demands, which forms the motivation of this review. Herein, the roles of membranes in different processes based on solar‐driven evaporation are focused and the design principles of membrane materials and devices to meet the requirements of these applications are discussed. Fabrication strategies for photothermal membranes are introduced primarily, followed by a discussion on how to design membrane materials, devices, and processes to pursue optimal performance and realize advanced functions accompanied by evaporation. Furthermore, the future of this field is forecast with both challenges and opportunities.
Solar steam generation holds great promise in alleviating fresh water crises, particularly in regions with accessible seawater and abundant insolation. Affordable, efficient, and environmentally ...friendly photothermal materials are needed to fabricate sunlight‐driven evaporation devices. Herein, Chinese ink, a carbon‐based paint used in traditional painting and calligraphy, is readily coated on diverse substrates and stabilized by atomic layer deposition (ALD) for solar steam generation. The ALD/Chinese ink coating exhibits strong and broad light absorption from the NIR to UV regions. Both ALD/Chinese‐ink‐coated membranes and wood display excellent photothermal properties and superior evaporation performance under simulated sunlight. This study demonstrates the potential of ALD/Chinese ink coating to achieve higher evaporation rate and efficiency by utilizing substrates with rough, structured surfaces and low thermal conductivity.
Chinese ink is applied on diverse materials and stabilized by atomic layer deposition to fabricate solar steam generation devices. The encapsulated ink has excellent photothermal properties and evaporation efficiency under simulated sunlight, holding great promise in solar evaporation device applications.
Through replacement of traditional energy sources with sunlight as the heat source, solar steam generation has emerged as a promising technology for water purification and residuals management. ...Despite significant efforts to develop efficient photothermal materials for solar steam devices, challenges associated with scalable fabrication of high‐performance materials remain. Moreover, most existing methods cannot be easily engineered to produce steam‐generating devices with both arbitrary control over shape and high photothermal efficiency. Herein, a flexible porphyrin organic framework (POF)‐based interface engineering method is introduced to produce high‐performance solar steam generators. POFs, a recently discovered class of materials, are demonstrated to grow readily on a diverse range of porous substrates, including membranes, fabrics, sponges, and wood. Wood@POF exhibits particularly strong performance, achieving ≈80% light‐to‐steam conversion efficiency. This study demonstrates a universal, simple, and scalable interface engineering strategy for the fabrication of solar steam generators based on POF materials.
A universal, simple, and scalable interface engineering strategy is demonstrated for the fabrication of a solar steam generators based on porphyrin covalent organic frameworks (POFs). POFs can grow uniformly and in situ on the surface of diverse materials with a range of different porosities. Wood@POF, using wood as the template, shows 80% overall efficiency for steam generation.
PDF
