Abstract: The invention relates to a method of patterning a substrate with graphene-based or other electroactive-material-based solution that includes solid-phase particles as hard templates, reducing the solution, and processing the reduced solution to expose the particles. The exposed hard template particles are removed to leave a three-dimensional (3D) porous architecture that can be beneficially used for a variety of applications, including but not limited to bio sensors and supercapacitors. In one example, the exposure is by etching with a CO2 laser. The method can be practiced with scalable MEMS fabrication technologies.

Abstract: Apparatus, systems, and methods for tuning the structure, conductivity, and/or wettability of laser induced graphene for a variety of functions including but not limited to multiplexed open microfluidic environmental biosensing and energy storage devices. Aspects of this invention introduce a one-step, mask-free process to create, pattern, and tune laser-induced graphene (LIG) with a ubiquitous CO2 laser or other laser. The laser parameters are adjusted to create LIG with different electrical conductivity, surface morphology, and surface wettability without the need for post chemical modification. This can be done with a single lasing. By optionally introducing a second (or third, fourth, or more) lasing(s), the LIG characteristics can be changed in just the same one step of using the laser scribing without other machines or sub-systems. One example is a second lasing with the same laser sub-system at low laser power, wherein the wettability of the LIG can be significantly altered.

Abstract: In a general aspect, an apparatus can include a first carbon nanotube array that is patterned to define a first electrode having a first plurality of electrode segments. The apparatus can also include a second carbon nanotube array that is patterned to define a second electrode having a second plurality of electrode segments. The second plurality of electrode segments can be interdigitated with the first plurality of electrode segments. The apparatus can further include a biorecognition agent disposed on a surface of the first electrode and disposed on a surface of the second electrode. The first plurality of electrode segments can each have a height-to-width aspect ratio of at least 1 to 1.

Abstract: Apparatus and methods of fabrication and use of highly effective laser-induced graphene (LIG) electrodes including for electrochemical sensing and catalysis. One example is a sensitive and label-free laser-induced graphene (LIG) electrode functionalized for a specific application. One example of functionalization with antibodies, an enzyme, or an ionophore to electrochemically quantify a target species The LIG electrodes were produced by laser induction on film having a carbon precursor (e.g. polyimide) in ambient conditions, and hence circumvent the need for high-temperature, vacuum environment, and metal seed catalysts commonly associated with graphene-based electrodes fabricated via chemical vapor deposition processes. These results demonstrate how LIG-based electrodes can be used for electrochemical sensing in general.

Abstract: Methods and systems of fabrication of high resolution, high-throughput electrochemical sensing circuits on a substrate. High resolution electrochemical sensing circuits are printed by an effective additive technique to the substrate. Optionally, post-print annealing converts electrochemically inactive printed graphene into one that is electrochemically active. The printing can be by aerosol jet printing, but is not necessarily limited thereto. An example is inkjet printing and then the post-print annealing. Ink formulation would be adjusted for effectiveness with inkjet printing. Optionally biorecognition agents can be covalently bonded to the printed graphene for the purpose of electrochemical biosensing. High throughput fabrication of high-resolution graphene circuits (feature sizes in the tens of microns <50 ?m) for electrochemical biosensing is possible by chemical functionalization of the graphene surface with a biological agent.

Abstract: An apparatus, method, and system for post-processing a printed graphene ink pattern or other deposition on a substrate. A pulsed UV laser is tunable between various energy densities to selectively modify the printed ink or deposition in electrical or physical properties. In one example, radical improvements in electrical conductivity are achieved. In another example, controlled transformation from essentially 2D printed or deposited graphene to surface topology of 3D nanostructures are achieved. The 3D structures are beneficial in such applications as electrochemical sensors of different types and characteristics. In another example, hydrophobicity of the printed or deposited graphene can be manipulated starting from a hydrophilic to super hydrophobic surface.

Abstract: Methods, systems, and compositions to produce high resolution, highly scalable patterns on a variety of substrates. A high resolution sacrificial negative of the desired pattern in inkjet printed on the substrate with an inkjet printable ink. A viscous solution is coated or deposited over the negative pattern and substrate. The solution is stabilized such as by drying and adheres to the substrate. The sacrificial negative is removed, leaving the dried solution in the high resolution form factor defined by the removed negative. This allows the solution to be formulated without regard to meeting inkjet printing requirements but results in a high resolution final positive pattern on the substrate.

Abstract: In a general aspect, an apparatus can include a first carbon nanotube array that is patterned to define a first electrode having a first plurality of electrode segments. The apparatus can also include a second carbon nanotube array that is patterned to define a second electrode having a second plurality of electrode segments. The second plurality of electrode segments can be interdigitated with the first plurality of electrode segments. The apparatus can further include a biorecognition agent disposed on a surface of the first electrode and disposed on a surface of the second electrode. The first plurality of electrode segments can each have a height-to-width aspect ratio of at least 1 to 1.

Abstract: Techniques, devices and systems are disclosed for implementing acoustically triggered propulsion of nano- and micro-scale structures. In one aspect, an ultrasound responsive propulsion device includes a tube that includes one or more layers including an inner layer having an electrostatic surface, and an ultrasound-responsive substance coupled to the inner layer and configured to form gaseous bubbles in a fluid in response to an ultrasound pulse, in which the bubbles exit the tube to propel the tube to move in the fluid.

Abstract: Techniques, devices and systems are disclosed for implementing acoustically triggered propulsion of nano- and micro-scale structures. In one aspect, an ultrasound responsive propulsion device includes a tube that includes one or more layers including an inner layer having an electrostatic surface, and an ultrasound-responsive substance coupled to the inner layer and configured to form gaseous bubbles in a fluid in response to an ultrasound pulse, in which the bubbles exit the tube to propel the tube to move in the fluid.