Related papers: Near-Field Enhanced Thermionic Energy Conversion f…
Solid-state heat-to-electrical power converters are thermodynamic engines that use fundamental particles, such as electrons or photons, as working fluids. Virtually all commercially available devices are thermoelectric generators, in which…
A huge amount of thermal energy is available close to material surfaces in radiative and non-radiative states, which can be useful for matter characterization or for energy devices. One way to harness this near-field energy is to scatter it…
Over the past years, thermionic energy conversion (TEC) with a reduced inter-electrode vacuum gap has been studied as an effective way to mitigate a large potential barrier due to space charge accumulation. However, existing theoretical…
Electric power may, in principle, be generated in a highly efficient manner from heat created by focused solar irradiation, chemical combustion, or nuclear decay by means of thermionic energy conversion. As the conversion efficiency of the…
The energy transferred via thermal radiation between two surfaces separated by nanometers distances (near-field) can be much larger than the blackbody limit. However, realizing a reconfigurable platform that utilizes this energy exchange…
This work investigates an alternative to thermophotovoltaics for harvesting thermal and optical energy via photon coupling and thermionic energy conversion. In this device, a heat source is radiatively coupled to a thermionic electron…
We present a systematic optimization of nighttime thermoelectric power generation system utilizing radiative cooling. We show that an electrical power density over 2 W/m2, two orders of magnitude higher than the previously reported…
Thermophotovoltaics, devices that convert thermal infrared photons to electricity, offer a key pathway for a variety of critical renewable energy technologies including thermal energy storage, waste heat recovery, and direct solar-thermal…
Numerical and semi-analytical models are presented for photon-enhanced-thermionic-emission (PETE) devices. The models take diffusion of electrons, inhomogeneous photogeneration, and bulk and surface recombination into account. The…
We present a comprehensive analysis of a dual, micro-gap thermionic-thermoelectric hybrid energy converter by developing a detailed theoretical model of the system. The Space-charge and near-field effects in thermionic conversion and the…
Thermionic energy conversion (TEC) using nano materials is an emerging field of research. Graphene can stand high temperature as high as 4600 K in vacuum. Its work function can be engineered from its high value (for monolayer/bilayer) 4.6…
Most attention to improving vacuum thermionic energy conversion device (TEC) technology has been on improving electron emission with little attention to collector optimization. A model was developed to characterize the output…
We propose a near-field inelastic thermoelectric heat engine where quantum-dots are used to effectively rectify the charge flow of photo-carriers. The device converts near-field heat radiation into useful electrical power. Heat absorption…
In the close vicinity of a hot body, at distances smaller than the thermal wavelength, a high electromagnetic energy density exists due to the presence of evanescent fields radiated by the partial charges in motion around its surface. This…
We show that the maximum work that can be obtained from the thermal radiation emitted between two planar sources in the near-field regime is much larger than that corresponding to the blackbody limit. This quantity as well as an upper bound…
A p-n junction maintained at above ambient temperature can work as a heat engine, converting some of the supplied heat into electricity and rejecting entropy by interband emission. Such thermoradiative cells have potential to harvest…
Thermionic converters generate electricity from thermal energy in a power cycle based on vacuum emission of electrons. While thermodynamically efficient, practical implementations are limited by the extreme temperatures required for…
Thermophotovoltaic devices are energy-conversion systems generating an electric current from the thermal photons radiated by a hot body. In far field, the efficiency of these systems is limited by the thermodynamic Schockley-Queisser limit…
Energy harvesting is a modern concept which makes dissipated heat useful by transferring thermal energy to other excitations. Most of the existing principles for energy harvesting are realized in systems which are heated continuously, for…
More than half of the waste heat rejected into the environment has temperatures lower than 100 $^\circ C$, which accounts for nearly 85 PWh/year worldwide. Efficiently harvesting low-grade heat could be a promising step toward carbon…