Parallel nanomanufacturing via electrohydrodynamic jetting from microfabricated externally-fed emitter arrays

Abstract

We report the design, fabrication, and characterization of planar arrays of externally-fed silicon electrospinning emitters for high-throughput generation of polymer nanofibers. Arrays with as many as 225 emitters and with emitter density as large as 100 emitters cm(-2) were characterized using a solution of dissolved PEO in water and ethanol. Devices with emitter density as high as 25 emitters cm(-2) deposit uniform imprints comprising fibers with diameters on the order of a few hundred nanometers. Mass flux rates as high as 417 g hr(-1) m(-2) were measured, i.e., four times the reported production rate of the leading commercial free-surface electrospinning sources. Throughput increases with increasing array size at constant emitter density, suggesting the design can be scaled up with no loss of productivity. Devices with emitter density equal to 100 emitters cm(-2) fail to generate fibers but uniformly generate electrosprayed droplets. For the arrays tested, the largest measured mass flux resulted from arrays with larger emitter separation operating at larger bias voltages, indicating the strong influence of electrical field enhancement on the performance of the devices. Incorporation of a ground electrode surrounding the array tips helps equalize the emitter field enhancement across the array as well as control the spread of the imprints over larger distances.

Direct electronetting of high-performance membranes based on self-assembled 2D nanoarchitectured networks

“…8. Although several pieces of similar networks can be found in holey/lacey carbon or cellulose nanocrystal films after instable polymer/solvent evaporation 26,27 , large-scale fabrication of such nanofibrous networks has never before been reported 46,47 . Here, we can easily fabricate a PVDF nano-net membrane with an area of 55 × 70 cm 2 (Supplementary Fig.…”

Customization of Electrospinning for Tissue Engineering

“…Different jet heads are used in the melt and the solution electrospinning: a nozzle (to provide wire or melt feeding) or a syringe (to provide solution flow). Different designs of the jet head are investigated aiming to provide efficient material feed, including composites [22,24]. Electrospun fibers have been investigated for different biomedical applications, such as drug delivery.…”

“…The type of the collector used in the process has significant influence on the distribution of the fibers, and further on the porous scaffold sample. Different types of collectors can be used for electrospinning process and new designs have been investigated, especially in combination with multiple electrospinning sources [22,24]. High voltage brought to the collector (or the needle) creates a very strong electric field which elongates the droplet and creates fibers that are further attached to the collector.…”

“…Biomimetic scaffolds were fabricated by using a complex collector with a stationary cylindrical hollow piece and a mobile internal cylinder which enabled circumferential and radial alignment of fibers [20]. Some recent applications of 3D printing are for production of complex shapes of collectors in order to enable novel shapes of electrospun fibrous mats [21], multiplexed electrospinning sources [22], structuring of scaffolds [23], or planar arrays of electrospinning emitters [24]. Development of different electrospinning techniques (meltand solution-electrospinning, force-spinning, melt-blowing, flash-spinning, spinning of bicomponent fibers) has become a hot topic due to versatile applications of micro-and nanofibers (tissue engineering, sensors, clothing, membranes for filtration systems, fillers in composite structures, coatings, etc.)…”

3D printed multiplexed electrospinning sources for large-scale production of aligned nanofiber mats with small diameter spread

“…Microfabrication technology can circumvent some of the manufacturing challenges faced by these systems including the tight control of the dimensions, the monolithic creation of the emitter arrays with the feedstock supply network, and the miniaturization of the emitters to achieve larger emitter density and operation at less bias voltage. In particular, Ponce de Leon et al reported a planar electrospinning emitter array made of silicon via deep reactive-ion etching with 225 emitters spaced 2 mm [35].…”