Tunable membranes incorporating artificial water channels for high-performance brackish/low-salinity water reverse osmosis desalination

Membrane-based technologies have a tremendous role in water purification and desalination. Inspired by biological proteins, artificial water channels (AWCs) have been proposed to overcome the permeability/selectivity trade-off of desalination processes. Promising strategies exploiting the AWC with angstrom-scale selectivity have revealed their impressive performances when embedded in bilayer membranes. Herein, we demonstrate that self-assembled imidazole-quartet (I-quartet) AWCs are macroscopically incorporated within industrially relevant reverse osmosis membranes. In particular, we explore the best combination between I-quartet AWC and m-phenylenediamine (MPD) monomer to achieve a seamless incorporation of AWC in a defect-free polyamide membrane. The performance of the membranes is evaluated by crossflow filtration under real reverse osmosis conditions (15 to 20 bar of applied pressure) by filtration of brackish feed streams. The optimized bioinspired membranes achieve an unprecedented improvement, resulting in more than twice (up to 6.9 L center dot m-2 center dot h-1 center dot bar-1) water permeance of analogous commercial membranes, while maintaining excellent NaCl rejection (>99.5%). They show also excellent performance in the purification of low-salinity water under low-pressure conditions (6 bar of applied pressure) with fluxes up to 35 L center dot m-2 center dot h-1 and 97.5 to 99.3% observed rejection

Biomimetic artificial water channel membranes for enhanced desalination

Inspired by biological proteins, artificial water channels (AWCs) can be used to overcome the performances of traditional desalination membranes. Their rational incorporation in composite polyamide provides an example of biomimetic membranes applied under representative reverse osmosis desalination conditions with an intrinsically high water-to-salt permeability ratio. The hybrid polyamide presents larger voids and seamlessly incorporates I–quartet AWCs for highly selective transport of water. These biomimetic membranes can be easily scaled for industrial standards (>m2), provide 99.5% rejection of NaCl or 91.4% rejection of boron, with a water flux of 75 l m−2 h−1 at 65 bar and 35,000 ppm NaCl feed solution, representative of seawater desalination. This flux is more than 75% higher than that observed with current state-of-the-art membranes with equivalent solute rejection, translating into an equivalent reduction of the membrane area for the same water output and a roughly 12% reduction of the required energy for desalination

Self-assembly of supramolecular triarylamine nanowires in mesoporous silica and biocompatible electrodes thereof

Biocompatible silica-based mesoporous materials, which present high surface areas combined with uniform distribution of nanopores, can be organized in functional nanopatterns for a number of applications. However, silica is by essence an electrically insulating material which precludes applications for electro-chemical devices. The formation of hybrid electroactive silica nanostructures is thus expected to be of great interest for the design of biocompatible conducting materials such as bioelectrodes. Here we show that we can grow supramolecular stacks of triarylamine molecules in the confined space of oriented mesopores of a silica nanolayer covering a gold electrode. This addressable bottom-up construction is triggered from solution simply by light irradiation. The resulting self-assembled nanowires act as highly conducting electronic pathways crossing the silica layer. They allow very efficient charge transfer from the redox species in solution to the gold surface. We demonstrate the potential of these hybrid constitutional materials by implementing them as biocathodes and by measuring laccase activity that reduces dioxygen to produce water

Facilitated transport of organics of biological interest II. Selective transport of organic acids by macrocyclic fixed site complexant membranes

International audienc

Pyrene-box capsules for adaptive encapsulation and structure determination of unstable or non-crystalline biogenic compounds

International audienc

ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY

International audienc

Membranes: Materials and Processes

International audienc