Inventor: SCHMIDT, Howard K.
(WO/2008/060640) NANOPARTICLE / NANOTUBE-BASED NANOELECTRONIC DEVICES AND CHEMICALLY-DIRECTED ASSEMBLY THEREOF
Pub. No.: WO/2008/060640 International Application No.: PCT/US2007/061563
Publication Date: 22.05.2008 International Filing Date: 02.02.2007
IPC: G02B 6/12 (2006.01)
Applicants: WILLIAM MARSH RICE UNIVERSITY [US/US]; 6100 Main Street, Houston, TX 77005 (US) (All Except US).
SCHMIDT, Howard K. [US/US]; 20702 Bradford Creek Ct, Cypress, TX 77433 (US) (US Only).
Inventor: SCHMIDT, Howard K. [US/US]; 20702 Bradford Creek Ct, Cypress, TX 77433 (US).
Agent: SHADDOX, Robert C.; Winstead Sechrest & Minick P.c., P.O. Box 50784, Dallas, TX 75201 (US).
60/764,636 02.02.2006 US
Title: NANOPARTICLE / NANOTUBE-BASED NANOELECTRONIC DEVICES AND CHEMICALLY-DIRECTED ASSEMBLY THEREOF
According to some embodiments, the present invention provides a nanoelectronic device based on a nanostructure that may include a nanotube with first and second ends, a metallic nanoparticle attached to the first end, and an insulating nanoparticle attached to the second end. The nanoelectronic device may include additional nanostructures so a to form a plurality of nanostructures comprising the first nanostructure and the additional nanostructures. The plurality of nanostructures may arranged in a network comprising a plurality of edges and a plurality of vertices, wherein each edge comprises a nanotube and each vertex comprises at least one insulating nanoparticle and at least one metallic nanoparticle adjacent the insulating nanoparticle. The combination of at least one edge and at least one vertex comprises a diode. The device may be an optical rectenna.
 An attraction for rectenna technology is its high theoretical conversion efficiency - roughly 95%. The greatest conversion efficiency ever recorded by a rectenna element occurred in 1977 by Brown, Raytheon Company. Using a GaAs-Pt Schottky barrier diode, a 90.6% conversion efficiency was recorded with an input microwave-power level of 8W. Conversion efficiencies in the range of 80% are typical, with representative circuits shown below.
 The concept is arbitrarily scaleable, and the optical rectenna is a direct extension to shorter wavelengths. Some of recent work in the area was performed by ITN energy systems [[For background see below!]] under DOE and DARPA sponsorship "BROADBAND OPTICAL RECTENNA FOR ENERGY HARVESTING", CECOM ENERGY HARVESTING PROGRAM Slides, April 14, 2000 ). Such micro- and nano-scale rectenna devices can convert ambient electromagnetic radiation (i.e. solar spectrum, blackbody radiators, active emitters) to DC electric power. The potential is to convert over 85% of the sun's energy to useable power compared to ~30% now achievable with conventional semiconductor based photovoltaics. Such devices may also be applicable to uncooled infrared detectors.
 While the concept has been proven in principal, useful power conversion in the optical frequency range is prevented by the low frequency response of the planar diodes employed.
 Thus there remains a need for optical rectennas having desirable frequency response and power conversion.
BRIEF DESCRIPTION OF THE INVENTION
 These and other features and advantages of the invention will be apparent to those skilled in the art from the following detailed description of various embodiments, taken together with the accompanying figures and claims, in which:
 According to some embodiments, the present invention provides a nanoelectronic device based on a nanostructure that may include a nanotube with first and second ends, a metallic nanoparticle attached to the first end, and an insulating nanoparticle attached to the second end.
 The nanotube may be conducting. Thus, it may be any one of conducting, semiconducting, and semi-metallic. Further, the nanotube may be a single walled nanotube or a multi-walled nanotube. The nanotube may be primarily carbon.
 The nanotube may absorb light. Yet further, the nanotube may be an antenna.
The length between the first and second ends is about half a wavelength of the light. The light may include at least one of visible and infrared radiation.
 The insulating nanoparticle may be formed of a metal oxide. The metallic nanoparticle may be formed of elemental metal.
3. The nanoelectronic device according to claim 1, wherein the nanotube absorbs light.
5. The nanolectronic device according to claim 4, wherein the length between the first and second ends is about half a wavelength of the light.
6. The nanolectronic device according to claim 5, wherein the light comprises at least one of visible and infrared radiation.
7. The nanolectronic device according to claim 1, wherein the insulating nanoparticle comprises a metal oxide.
8. The nanolectronic device according to claim 1, wherein the metallic nanoparticle comprises elemental metal.
9. The nanolectronic device according to claim 1, wherein the nanoelectronic device further comprises additional nanostructures so a to form a plurality of nanostructures comprising the first nanostructure and the additional nanostructures.
11. The nanolectronic device according to claim 10, wherein the combination of at least one edge and at least one vertex comprises a diode.
12. The nanolectronic device according to claim 9, wherein the device is an optical rectenna.
13. A nanoelectronic device comprising an optical rectenna comprising a plurality of nanostructures arranged so as to form a plurality of nanoscale diodes with integrated antennas, wherein each nanostructure comprises:
14. The nanoelectronic device according to claim 13, wherein the conducting nanotube is metallic.
15. The nanoelectronic device according to claim 13, wherein the conducting nanotube is semi-metallic.
16. The nanoelectronic device according to claim 13, wherein the conducting nanotube is semi-conducting.
17. The nanoelectronic device according to claim 13, wherein the conducting nanotube is a single-walled nanotube.
18. The nanoelectronic device according to claim 13, wherein the conducting nanotube is a multi-walled nanotube.
19. A method of making a nanoelectronic device, comprising: making a plurality of asymmetric nanostructures, wherein making the plurality of nanostructures comprises: providing a plurality of nanotubes, each having a first end functionalized with at least one functionalizing moiety and a second end having a linker molecule attached thereto; attaching a metallic nanoparticle to the linker molecule; and attaching an insulating nanoparticle to the functionalizing moiety.
20. The method according to claim 17, comprising: aligning the plurality of nanostructures so as to form an oriented network.
BACKGROUND - ITN Energy Systems:
Photovoltaic Technologies Beyond the Horizon
Optical Rectenna Solar Cell
1. Background on ITN Energy Systems’ Optical Rectenna Technology
1.1. Motivation for Next-Generation, High-Efficiency Solar Cells
Worldwide energy demands have increased by 40% over the last 20 years.1 Although the deleterious effects of hydrocarbon-based power are becoming increasingly apparent, more than 85% of the world’s power is still generated by combustion of fossil fuels.1 Clean renewable alternative energy sources are required to meet the demands, with direct solar-conversion devices as leading candidates. The worldwide market for conventional photovoltaics (PV) has increased at an annual rate of 20% over the last five years, and industry estimates suggest as much as 18 billion watts per year could ship by 2020.1 To meet the increased demands for solar-conversion technologies, dramatic improvements are required in state-of-the-art PV technologies. Efficiency improvements and cost/complexity reduction are the main issues that need to be addressed to meet these goals.
Traditional p-n junction solar cells are the most mature of the solar-energy-harvesting technologies. Although great improvements have been made in the last 20 years, energy absorption, carrier generation, and collection are all a function of the materials chemistry and corresponding electronic properties (i.e., bandgap). As a quantum device, the efficiency of PV is a function of, and therefore, ultimately fundamentally limited by, the bandgap and the match of the bandgap to the solar spectrum. For single-junction cells, this sets an upper efficiency limit of ~30%.2 Even with complex multi-junction designs, the theoretical efficiency plateaus around 55% without excessive concentration of the incident radiation.3 Current state-of-the-art solar cells are ~20% efficient for single cells and ~30% efficient for multijunction systems.4 In the long term, the PV industry will require newer, higher efficiency technologies to improve performance and to meet the increasing demands of the solar power market.
As an alternative, ITN Energy Systems is developing next-generation solar cells based on the concepts of an optical rectenna (see Figure 1). ITN’s optical rectenna consists of two key elements: 1) an optical antenna to efficiently absorb the incident solar radiation, and 2) a highfrequency metal-insulator-metal (MIM) tunneling diode that rectifies the AC field across the antenna, providing DC power to an external load. The combination of a rectifying diode at the feedpoints of a receiving antenna is often referred to as a rectenna. Rectennas were originally proposed in the 1960s for power transmission by radio waves for remote powering of aircraft for surveillance or communications platforms.5 Conversion efficiencies greater than 85% have been demonstrated at radio frequencies (efficiency defined as DC power generated divided by RF power incident on the device). Later, concepts were proposed to extend the rectennas into the infrared (IR) and optical region of the electromagnetic spectrum for use as energy collection devices (optical rectennas).6
BACKGROUND: Boston College - Ren; Zhifeng
|United States Patent Application||20070240757|
|Ren; Zhifeng ; et al.||October 18, 2007|
Solar cells using arrays of optical rectennas
The present invention discloses a solar cell comprising a nanostructure array capable of accepting energy and producing electricity. In an embodiment, the solar cell comprises an at least one optical antenna having a geometric morphology capable of accepting energy. In addition, the cell comprises a rectifier having the optical antenna at a first end and engaging a substrate at a second end wherein the rectifier comprises the optical antenna engaged to a rectifying material (such as, a semiconductor). In addition, an embodiment of the solar cell comprises a metal layer wherein the metal layer surrounds a length of the rectifier, wherein the optical antenna accepts energy and converts the energy from AC to DC along the rectifier. Further, the invention provides various methods of efficiently and reliably producing such solar cells.
|Inventors:||Ren; Zhifeng; (Newton, MA) ; Kempa; Krzysztof; (Billerica, MA) ; Wang; Yang; (Allston, MA)|
The presently disclosed embodiments generally relate to the use of nano-coaxial transmission lines (NCTL) to fabricate a nano-optics apparatus. The nano-optics apparatus is a multifunctional nano-composite material made of a metallic film having a top surface and a bottom surface and a plurality of cylindrical channels filled with a dielectric material. An array of nanorods penetrate the metallic film through the plurality of cylindrical channels. The array of nanorods has a protruding portion that extends beyond a surface of the metallic film and an embedded portion that is within the metallic film. The protruding portion acts as a nano-antenna and is capable of receiving and transmitting an electromagnetic radiation at a visible frequency. The embedded portion acts as a nano-coaxial transmission line (CTL) and allows for propagation of external radiation with a wavelength exceeding the perpendicular dimensions of the nanorod.
The nano-optics apparatus can concentrate light, and therefore enhance a field up to about 103 times. The array of optical nano-antennas, with nano-CTL embedded in a metallic film, effectively compresses light into nanoscopic dimensions. The nano-antennas are capable of receiving and transmitting an electromagnetic radiation at the visible frequencies. The extreme compression of light in the nano-CTL leads to an asymmetric tunneling of electrons between the electrodes of the nano-CTL, and thus provides a rectifying action at the light frequencies, and thus conversion of the light into a direct current (DC) voltage. This property leads to a new class of efficient, and low cost rectenna solar cells. The extreme compression of light in the nano-CTL is quick, and is not limited by the usual parasitic capacitances that make the conventional diode rectification inefficient, if not impossible, at the light frequencies.
And these, as well:
Submitted for the MAR08 Meeting of The American Physical Society
Nanocoax Solar Cells1 M.J. NAUGHTON, K. KEMPA, Z.F. REN, J. RYBCZYNSKI2, T. PAUDEL, Y. GAO, Y. XU, Boston College
A novel architecture for high effciency solar energy conversion, employing separated photo- and -voltaic pathways and antenna-based light collection, is described.
Dr. Howard K. Schmidt Bio:
Dr. Howard K. Schmidt, Executive Director of the Carbon Nanotechnologies Laboratory
Howard Schmidt is the Executive Director of the Carbon Nanotechnology Laboratory (CNL) at Rice University. He is an expert in the field of carbon nanotechnology and single-wall carbon nanotubes, one of the most versatile materials on the nanotechnology horizon. At the CNL, Dr. Schmidt is responsible for developing and managing key federal and industrial relationships to drive emerging applications for carbon nanotubes. He serves on the Board of Directors of Axion Power Corporation (member of Audit and Technology Committees), and the Advisory Board of Texas Nanotech Ventures (Chairman). He also serves occasionally as an Expert Witness or Technology Advisor in patent litigation.
Schmidt's current research and development projects focus on nanostructured carbon and metallic materials for structural composites, energy storage and solar cells.
Prior to joining the CNL, Schmidt founded or co-launched four technology companies over seventeen years: Ionwerks, SI Diamond Technology (SIDT), EQUEX and Road-Show.Com. Schmidt took SIDT public in 1993; the firm (now called NanoProprietary) is a long-time leader in developing nanotechnology applications.
Schmidt holds a Bachelors' in Electrical Engineering (1980) and a Doctorate in Physical Chemistry (1986), both from Rice University.http://www.tntventures.com/schmidt.html
(Note 'Zvi Yaniv')
You know - when I see this kinda statement --The potential is to convert over 85% of the sun's energy to useable power compared to ~30% now achievable-- I get all tingly with excitement, sell oil short and believe in sugarplum fairies!!
And go talk to grandpa just to say hello....and maybe see what's up, too.
The wallet needs filling!
Did you notice Schmidt and Ren are both using CNTs!!!
Hello grandpa!!!! Come back to NNPP. Bring Boston College and Ren et al with you!!