3D printed gradient index glass optics.

We demonstrate an additive manufacturing approach to produce gradient refractive index glass optics. Using direct ink writing with an active inline micromixer, we three-dimensionally print multimaterial green bodies with compositional gradients, consisting primarily of silica nanoparticles and varying concentrations of titania as the index-modifying dopant. The green bodies are then consolidated into glass and polished, resulting in optics with tailored spatial profiles of the refractive index.

Three-Dimensional Printable Sodium Carbonate Composite Sorbents for Efficient Biogas Upgrading.

We have developed a new class of sodium carbonate/silicone composite sorbents that selectively capture carbon dioxide (CO) and can purify biogas to natural gas pipeline-quality biomethane. These nontoxic composites can be three-dimensionally printed or extruded at low costs, can have high specific CO sorption rates (in excess of 5 μmol s g bar) and high selectivity due to their chemical mechanism, and can be regenerated with low-energy air stripping. Therefore, these composite sorbents combine the high selectivity of liquid sorbents with the high specific sorption rates and low regeneration energies found in many solid sorbents.

Additive Manufacturing of Optical Quality Germania-Silica Glasses.

Direct ink writing (DIW) three-dimensional (3D) printing provides a revolutionary approach to fabricating components with gradients in material properties. Herein, we report a method for generating colloidal germania feedstock and germania-silica inks for the production of optical quality germania-silica (GeO-SiO) glasses by DIW, making available a new material composition for the development of multimaterial and functionally graded optical quality glasses and ceramics by additive manufacturing. Colloidal germania and silica particles are prepared by a base-catalyzed sol-gel method and converted to printable shear-thinning suspensions with desired viscoelastic properties for DIW.

Parallelizable microfluidic dropmakers with multilayer geometry for the generation of double emulsions.

Microfluidic devices enable the production of uniform double emulsions with control over droplet size and shell thickness. However, the limited production rate of microfluidic devices precludes the use of monodisperse double emulsions for industrial-scale applications, which require large quantities of droplets. To increase throughput, devices can be parallelized to contain many dropmakers operating simultaneously in one chip, but this is challenging to do for double emulsion dropmakers.

Evaluating the Performance of Micro-Encapsulated CO Sorbents during CO Absorption and Regeneration Cycling.

We encapsulated six solvents with novel physical and chemical properties for CO sorption within gas-permeable polymer shells, creating Micro-Encapsulated CO Sorbents (MECS), to improve the CO absorption kinetics and handling of the solvents for postcombustion CO capture from flue gas. The solvents were sodium carbonate (NaCO) solution, uncatalyzed and with two different promoters, two ionic liquid (IL) solvents, and one CO-binding organic liquid (COBOL). We subjected each of the six MECS to multiple CO absorption and regeneration cycles and measured the working CO absorption capacity as a function of time to identify promising candidate MECS for large-scale carbon capture.

Custom 3D Printable Silicones with Tunable Stiffness.

Silicone elastomers have broad versatility within a variety of potential advanced materials applications, such as soft robotics, biomedical devices, and metamaterials. A series of custom 3D printable silicone inks with tunable stiffness is developed, formulated, and characterized. The silicone inks exhibit excellent rheological behavior for 3D printing, as observed from the printing of porous structures with controlled architectures.

3D-Printed Transparent Glass.

Silica inks are developed, which may be 3D printed and thermally processed to produce optically transparent glass structures with sub-millimeter features in forms ranging from scaffolds to monoliths. The inks are composed of silica powder suspended in a liquid and are printed using direct ink writing. The printed structures are then dried and sintered at temperatures well below the silica melting point to form amorphous, solid, transparent glass structures.

Microencapsulation of advanced solvents for carbon capture.

Purpose-designed, water-lean solvents have been developed to improve the energy efficiency of CO capture from power plants, including CO-binding organic liquids (COBOLs) and ionic liquids (ILs). Many of these solvents are highly viscous or change phases, posing challenges for conventional process equipment. Such problems can be overcome by encapsulation.

Three-dimensional conformal coatings through the entrapment of polymer membrane precursors.

We report a technique to coat polymers onto 3D surfaces distinct from traditional spray, spin, or dip coating. In our technique, the surface of a template structure composed of poly(lactic acid) swells and entraps a soluble polymer precursor. Once entrapped, the precursor is cured, resulting in a thin, conformal membrane.

A microvascular system for chemical reactions using surface waste heat.

Coffee-powered chemistry: Low-grade waste heat on surfaces can be used to drive chemical reactions, including the regeneration of a CO2 capture solution. Flowing two-phase heat transfer has been implemented within microvascular systems. This stripping system can be adapted to pre-fabricated surfaces, as demonstrated by a coffee mug containing a 1.

Process of making three-dimensional microstructures using vaporization of a sacrificial component.

Vascular structures in natural systems are able to provide high mass transport through high surface areas and optimized structure. Few synthetic material fabrication techniques are able to mimic the complexity of these structures while maintaining scalability. The Vaporization of a Sacrificial Component (VaSC) process is able to do so.

A three-dimensional microvascular gas exchange unit for carbon dioxide capture.

For the capture of CO(2) from mixed gas streams, materials for increased gas exchange are necessary. Efficient gas exchange systems already exist in the form of vascularized lung-tissue. Herein we report a fabrication technique for the synthesis of three-dimensional microvascular gas exchange units capable of removing CO(2) from flowing gas created using the recently reported Vaporization of a Sacrificial Component (VaSC) technique.