Spraying asymmetry into functional membranes layer-by-layer

Abstract

As engineers strive to mimic the form and function of naturally occurring materials with synthetic alternatives, the challenges and costs of processing often limit creative innovation. Here we describe a powerful yet economical technique for developing multiple coatings of different morphologies and functions within a single textile membrane, enabling scientists to engineer the properties of a material from the nanoscopic level in commercially viable quantities. By simply varying the flow rate of charged species passing through an electrospun material during spray-assisted layer-by-layer deposition, individual fibres within the matrix can be conformally functionalized for ultrahigh-surface-area catalysis, or bridged to form a networked sublayer with complimentary properties. Exemplified here by the creation of selectively reactive gas purification membranes, the myriad applications of this technology also include self-cleaning fabrics, water purification and protein functionalization of scaffolds for tissue engineering.

Recent advances in conjugated polymer energy storage

“…163,164 With the advent of spray layer-bylayer assembly, 165 composites such as these could be rapidly manufactured on an industrial scale onto many substrates or even applied as paint. 9,[163][164][165][166] PANI is also a promising material for composites with high capacity inorganic materials that lack ionic and electronic conductivity. 23,167,168 Our group has recently combined PANI and vanadium pentoxide in a layer-by-layer electrode (Fig.…”

Super-resolution surface mapping using the trajectories of molecular probes

“…S urface modification has become a critical component of micro-and nanofabrication with applications in technologies ranging from biodetection 1,2 to catalysis 3,4 and many more [5][6][7][8] . Many of these applications exploit non-covalent interactions and molecular recognition.…”

Spray‐Assisted Polyelectrolyte Multilayer Buildup: from Step‐by‐Step to Single‐Step Polyelectrolyte Film Constructions

“…The concept of reactive step-by-step process leading to the formation of mixed polyelectrolyte/oxide nanoparticle coatings was of electrospun fibers. [68] Compared to the LbL method by dipping, the spraying process may impair the production of conformal coatings of the fibers. [69] To circumvent this drawback the authors proposed to realize the spraying process under a pressure gradient across the membrane by applying a vacuum on the rear side of the membrane.…”