Multi-layered radio-isotope for enhanced photoelectron avalanche process

Patent metadata

Field	Value
Publication number	US-11257604-B2
Application number	US-201916426345-A
Country	US
Kind code	B2
Filing date	May 30, 2019
Priority date	May 30, 2018
Publication date	Feb 22, 2022
Grant date	Feb 22, 2022

Abstract

The present disclosure is directed to a nuclear thermionic avalanche cell (NTAC) systems and related methods of generating energy comprising a radioisotope core, a plurality of thin-layered radioisotope sources configured to emit high energy beta particles and high energy photons, and a plurality of NTAC layers integrated with the radioisotope core and the radioisotope sources, wherein the plurality of NTAC layers are configured to receive the beta particles and the photons from the radioisotope core and sources, and by the received beta particles and photons, free up electrons in an avalanche process from deep and intra bands of an atom to output a high density avalanche cell thermal energy through a photo-ionic or thermionic process of the freed up electrons.

First claim

What is claimed is:

1. A nuclear thermionic avalanche cell (NTAC) system comprising:
a radioisotope core comprised of a nuclear radioisotope material, wherein the radioisotope core is surrounded by a core thin emitter layer comprising an emitter material;
a plurality of radioisotope source layers, the radioisotope core and the plurality of radioisotope source layers configured to emit energetic beta particles and high energy photons, wherein each of the plurality of radioisotope source layers comprise:
an inner thin emitter layer, the inner thin emitter layer comprising the emitter material;
an outer thin emitter layer, the outer thin emitter layer comprising the emitter material; and
a radiation source layer comprised of the nuclear radioisotope material, the radiation source layer disposed between the inner thin emitter layer and the outer thin emitter layer such that the radiation source layer surrounds the inner thin emitter layer and the outer thin emitter layer surrounds the radiation source layer,

wherein the plurality of radioisotope source layers are arranged concentrically around the radioisotope core such that a plurality of vacuum gaps are created where one of the plurality of vacuum gaps is created between an inner most one of the plurality of radioisotope layers and the radioisotope core and each remaining of the plurality of vacuum gaps is created between pairs of the plurality of radioisotope layers;
a plurality of collectors comprised of a collector material, one of the plurality of collectors disposed in each of the plurality of vacuum gaps, the plurality of collectors spaced within each of their respective ones of the plurality of vacuum gaps so as to not contact the radioisotope core or radioisotope source layers; and
a plurality of NTAC layers integrated with the radioisotope core and the radioisotope source layers, the plurality of NTAC layers each having at least one NTAC emitter layer comprising the emitter material, wherein:
the plurality of NTAC layers are configured to receive the energetic beta particles and the high energy photons, and by the received energetic beta particles and the high energy photons free up electrons to an avalanche process from deep and intra bands of atoms of the emitter material to output thermal energy through a photo-ionic or thermionic process of the freed up electrons; and
the plurality of NTAC layers are arranged concentrically around the radioisotope core and the plurality of radioisotope layers such that the plurality of radioisotope layers are disposed between the radioisotope core and the plurality of NTAC layers.

2. The system of claim 1 , wherein the energetic beta particles are electrons or positrons.

3. The system of claim 1 , wherein the high energy photons are x-rays, gamma rays, or UV light.

4. The system of claim 1 , wherein the nuclear radioisotope material is Cobalt-60, Sodium-22, or Cesium-137.

5. The system of claim 1 , wherein the core thin emitter layer, the inner thin emitter layers, and the outer thin emitter layers are configured to capture and interact with the energetic beta particles and the high energy photons released from the radioisotope core and the plurality of radioisotope source layers.

6. The system of claim 5 , wherein the emitter material comprises a nanostructured surface of a high Z material.

7. The system of claim 6 , wherein the plurality of collectors are configured to capture the energetic beta particles and/or the high energy photons emitted from the core thin emitter layer, the inner thin emitter layers, and the outer thin emitter layers, and wherein the plurality of NTAC layers is a number of NTAC layers selected such that all photon energy is depleted to a zero level without escaping the plurality of NTAC layers.

8. The system of claim 7 , wherein the collector material comprises a low or mid Z material.

9. The system of claim 1 , wherein each of the plurality of radioisotope source layers have a thickness from about 3 mm to about 5 mm.

10. The system of claim 9 , wherein the plurality of radioisotope source layers is two radioisotope source layers, the plurality of NTAC layers is five NTAC layers, the emitter material is gadolinium or a high Z material, and the collector material is copper.

11. The system of claim 1 , further comprising:
a metallic junction layer arranged around a NTAC layer of the plurality of NTAC layers farthest from the radioisotope core such that the plurality of NTAC layers are disposed between the plurality of radioisotope layers and the metallic junction layer;
a top cap; and
a bottom cap, the top cap and the bottom cap including radiation shielding layers and the tope cap and the bottom cap arranged to interface with the metallic junction layer such that the top cap, the bottom cap, and the metallic junction layer together encase the radioisotope core, the plurality of radioisotope layers, the plurality of collectors, and the plurality of NTAC layers,
wherein a metallic junction thermoelectric generator is configured to receive the output thermal energy from the plurality of NTAC layers via the metallic junction layer and output thermoelectric power.

Assignees

• Nasa

Inventors

• Choi Sang H
• Bushnell Dennis M
• Komar David R
• Hendricks Robert C

Classifications

• G21G1/12

  by electromagnetic irradiation, e.g. with gamma or X-rays (applications of radiation G21H5/00; irradiation devices G21K5/00) · CPC title

• G21H1/04 Primary

  Cells using secondary emission induced by alpha radiation, beta radiation, or gamma radiation · CPC title

• G21H1/12

  Cells using conversion of the radiation into light combined with subsequent photoelectric conversion into electric energy · CPC title

• G21G2001/0094

  Other isotopes not provided for in the groups listed above · CPC title

• G21G2001/0068

  Cesium · CPC title