Abstract: A nanoscale plate structure includes base plates and rib plates with nanoscale thickness and macroscopic lateral dimensions. The base plate resides in the first plane, the ribs can reside out-of-plane and form at least one strengthening rib, and additional base plates can reside in planes parallel to the first plane. The strengthening rib can be patterned such that there is no straight line path extending through a lateral dimension of the plate structure that does not intersect the at least one base plate and the at least one strengthening rib. The plates and ribs used in the structure have a thickness between about 1 nm and about 100 nm. The plate structures can be fabricated using a conformal deposition method including atomic layer deposition.

Abstract: A small-gap device system, preferably including two or more electrodes and one or more spacers maintaining a gap between two or more of the electrodes. A spacer for a small-gap device system, preferably including a plurality of legs defining a mesh structure. A method of spacer and/or small-gap device fabrication, preferably including: defining lateral features, depositing spacer material, selectively removing spacer material, separating the spacer from a fabrication substrate, and/or assembling the small-gap device.

Abstract: A small-gap device system, preferably including two or more electrodes and one or more spacers maintaining a gap between two or more of the electrodes. A spacer for a small-gap device system, preferably including a plurality of legs defining a mesh structure. A method of spacer and/or small-gap device fabrication, preferably including: defining lateral features, depositing spacer material, selectively removing spacer material, separating the spacer from a fabrication substrate, and/or assembling the small-gap device.

Abstract: A small-gap device system, preferably including two or more electrodes and one or more spacers maintaining a gap between two or more of the electrodes. A spacer for a small-gap device system, preferably including a plurality of legs defining a mesh structure. A method of spacer and/or small-gap device fabrication, preferably including: defining lateral features, depositing spacer material, selectively removing spacer material, separating the spacer from a fabrication substrate, and/or assembling the small-gap device.

Abstract: Systems and methods for achieving levitation via a photophoretic effect are provided. In certain embodiments, a structure of ultralight materials is provided, for example a BoPET film and carbon nanotubes and has a top and bottom side, made of two separate materials. When the bottom side is illuminated by light at certain intensity, it can result in an upward lift force being applied to the entire structure, causing the structure to levitate.

Abstract: A nanoscale plate structure includes base plates and rib plates with nanoscale thickness and macroscopic lateral dimensions. The base plate resides in the first plane, the ribs can reside out-of-plane and form at least one strengthening rib, and additional base plates can reside in planes parallel to the first plane. The strengthening rib can be patterned such that there is no straight line path extending through a lateral dimension of the plate structure that does not intersect the at least one base plate and the at least one strengthening rib. The plates and ribs used in the structure have a thickness between about 1 nm and about 100 nm. The plate structures can be fabricated using a conformal deposition method including atomic layer deposition.

Abstract: A small-gap device system, preferably including two or more electrodes and one or more spacers maintaining a gap between two or more of the electrodes. A spacer for a small-gap device system, preferably including a plurality of legs defining a mesh structure. A method of spacer and/or small-gap device fabrication, preferably including: defining lateral features, depositing spacer material, selectively removing spacer material, separating the spacer from a fabrication substrate, and/or assembling the small-gap device.

Abstract: The embodiments provide a thermionic emission device and a method for tuning a work function in a thermionic emission device is provided. The method includes illuminating an N type semiconductor material of a first member of a thermionic emission device, wherein a work function of the N type semiconductor material is lowered by the illuminating. The method includes collecting, on one of the first member or a second member of the thermionic emission device, electrons emitted from one of the first member or the second member.

Abstract: A small-gap device system, preferably including two or more electrodes and one or more spacers maintaining a gap between two or more of the electrodes. A spacer for a small-gap device system, preferably including a plurality of legs defining a mesh structure. A method of spacer and/or small-gap device fabrication, preferably including: defining lateral features, depositing spacer material, selectively removing spacer material, separating the spacer from a fabrication substrate, and/or assembling the small-gap device.

Abstract: The embodiments provide a thermionic emission device and a method for tuning a work function in a thermionic emission device is provided. The method includes illuminating an N type semiconductor material of a first member of a thermionic emission device, wherein a work function of the N type semiconductor material is lowered by the illuminating. The method includes collecting, on one of the first member or a second member of the thermionic emission device, electrons emitted from one of the first member or the second member.

Abstract: A nanoscale plate structure includes base plates and rib plates with nanoscale thickness and macroscopic lateral dimensions. The base plate resides in the first plane, the ribs can reside out-of-plane and form at least one strengthening rib, and additional base plates can reside in planes parallel to the first plane. The strengthening rib can be patterned such that there is no straight line path extending through a lateral dimension of the plate structure that does not intersect the at least one base plate and the at least one strengthening rib. The plates and ribs used in the structure have a thickness between about 1 nm and about 100 nm. The plate structures can be fabricated using a conformal deposition method including atomic layer deposition.

Abstract: A small-gap device system, preferably including two or more electrodes and one or more spacers maintaining a gap between two or more of the electrodes. A spacer for a small-gap device system, preferably including a plurality of legs defining a mesh structure. A method of spacer and/or small-gap device fabrication, preferably including: defining lateral features, depositing spacer material, selectively removing spacer material, separating the spacer from a fabrication substrate, and/or assembling the small-gap device.

Abstract: The presently disclosed subject matter relates to nanocardboard structures and methods of fabrication thereof. An exemplary nanocardboard structure includes at least two parallel planar films and webbing. The planar films can be separated from each other by a gap of from about 0.1 micrometers to about 1000 micrometers.

Abstract: A nanoscale plate structure includes base plates and rib plates with nanoscale thickness and macroscopic lateral dimensions. The base plate resides in the first plane, the ribs can reside out-of-plane and form at least one strengthening rib, and additional base plates can reside in planes parallel to the first plane. The strengthening rib can be patterned such that there is no straight line path extending through a lateral dimension of the plate structure that does not intersect the at least one base plate and the at least one strengthening rib. The plates and ribs used in the structure have a thickness between about 1 nm and about 100 nm. The plate structures can be fabricated using a conformal deposition method including atomic layer deposition.

Abstract: A nanoscale plate structure includes base plates and rib plates with nanoscale thickness and macroscopic lateral dimensions. The base plate resides in the first plane, the ribs can reside out-of-plane and form at least one strengthening rib, and additional base plates can reside in planes parallel to the first plane. The strengthening rib can be patterned such that there is no straight line path extending through a lateral dimension of the plate structure that does not intersect the at least one base plate and the at least one strengthening rib. The plates and ribs used in the structure have a thickness between about 1 nm and about 100 nm. The plate structures can be fabricated using a conformal deposition method including atomic layer deposition.

Abstract: The presently disclosed subject matter relates to nanocardboard structures and methods of fabrication thereof. An exemplary nanocardboard structure includes at least two parallel planar films and webbing. The planar films can be separated from each other by a gap of from about 0.1 micrometers to about 1000 micrometers.

Abstract: A small-gap device system, preferably including two or more electrodes and one or more spacers maintaining a gap between two or more of the electrodes. A spacer for a small-gap device system, preferably including a plurality of legs defining a mesh structure. A method of spacer and/or small-gap device fabrication, preferably including: defining lateral features, depositing spacer material, selectively removing spacer material, separating the spacer from a fabrication substrate, and/or assembling the small-gap device.

Abstract: A nanoscale plate structure includes base plates and rib plates with nanoscale thickness and macroscopic lateral dimensions. The base plate resides in the first plane, the ribs can reside out-of-plane and form at least one strengthening rib, and additional base plates can reside in planes parallel to the first plane. The strengthening rib can be patterned such that there is no straight line path extending through a lateral dimension of the plate structure that does not intersect the at least one base plate and the at least one strengthening rib. The plates and ribs used in the structure have a thickness between about 1 nm and about 100 nm. The plate structures can be fabricated using a conformal deposition method including atomic layer deposition.

Abstract: Improved thermionic energy converters are provided by electrodes that include a silicon carbide support structure, a tungsten adhesion layer disposed on the silicon carbide support structure, and an activation layer disposed on the tungsten adhesion layer. The activation layer is a material that lowers the electrode work function, such as BaO, SrO and/or CaO.

Abstract: A thermionic energy converter is provided that includes an anode, a cathode, where the anode is disposed opposite the cathode, and a suspension, where a first end of the suspension is connected to the cathode and a second end of the suspension is connected to the anode, where the suspension moveably supports the cathode above the anode to form a variable gap between the anode and the cathode, where the variable gap is capable of enabling a variable thermionic current between the anode and the cathode, where the thermionic converter is capable of an AC power output.