Kaskela A.,Aalto University |
Nasibulin A.G.,Aalto University |
Timmermans M.Y.,Aalto University |
Aitchison B.,Canatu Oy |
And 8 more authors.
Nano Letters | Year: 2010
We demonstrate an aerosol CVD process to dry deposit large-area SWCNT networks with tunable conductivity and optical transmittance on a wide range of substrates including flexible polymers. These SWCNT networks can be chemically doped to reach a sheet resistance of as low as 110 Ω/ at 90% optical transmittance. A wide application potential of these networks is demonstrated by fabricating SWCNT network-based devices such as a transparent capacitive touch sensors, thin-film transistors (TFTs), and bright organic light-emitting diodes (OLEDs). © 2010 American Chemical Society.
Agency: Department of Energy | Branch: | Program: STTR | Phase: Phase I | Award Amount: 150.00K | Year: 2013
Solar water heaters are a well-established renewable energy technology that has been widely adopted outside of the United States. Here we propose to significantly improve the evacuated solar tube collectors (ETC) by utilizing the dry-drawable carbon nanotube (CNT) sheets for solar energy absorption and CNT multifunctional nanocomposites with functional layers of heat accumulators and heat transporters. The benefits of the proposed carbon nanotube based solar water heaters is the property of carbon nanotubes as a near blackbody absorber, allowing the absorption of & gt;98% of the solar energy. In addition the porous nature of the sheets and nanometer diameter of tubes, increases light scattering inside the selective layer, resulting in light trapping, decreased reflectivity and increased light absorption. In this project we will be using large scale dry-drawable CNT sheets as multifunctional Absorbance layer on ETC, improving it further by birolling into its porous network functional layers of heat accumulation phase change material (PCM) microspheres and heat transfer sub-layer. In addition to being excellent blackbody absorbers, carbon nanotube sheets are a fast source of Joule heating (upon transmission of electrical current) and can be utilized to heat electrically the solar collectors when sunlight is not sufficient. Electrical connections can be made to the preferentially sectioned copper buffer layer to define the surface area for Joule heating. Such improvement would entirely eliminate the need for a separate gas or electric booster water heating system, by incorporating electric heating directly into the solar collector. A critical part of the proposed solar collector tube is the absorbing layer that is composed of CNT sheets. Developed in University of Texas at Dallas and licensed to Solarno, CNTs are grown as vertically oriented forests on iron-coated silicon wafer using chemical vapor deposition (CVD). Our RF-inductrive controllable CVD method for MWNT growth can be easily scaled to commercial level and reduce the manufacturing cost to the cost of the CVD process gases. In addition, the added value and savings of using the carbon nanotube based solar heater without the additional booster hardware would significantly decrease the payback period. According to a major manufacturer of solar water heaters, the payback period for a solar water heater with the current 57.1% efficiency solar collector tubes is 4-5 years. Upon successful implementation of the carbon nanotube sheets as the collector material and improved efficiency, we strongly believe that the payback period will remain less than 5 years. The ultimate goal of our research is to increase the usage of solar water heaters SWH in USA and achieve fast return on highly effective evacuated tube collectors ETC of SWH by using nanomaterials for light absorbing, conversion to heat, heat accumulation and heat transfer layers in ETC. our preliminary results has proven the validity of PCM incorporation into CNT- based absorber. Also birolling graphene flakes has proven to be beneficial for high thermal conductivity of CNT-based coatings. Our commercial partners, Apricus Solar and Westech Solar have generously provided us with parts of ETC and components for testing, and will be evaluating further this new technology for licensing and commercialization. Moreover Solarno will create RF-CVD systems for upscaling the growth of CNT sheets for commercial scale testing of full length 7 ft ETC in SWH panels.
Solarno, Inc | Date: 2015-05-07
An apparatus and method for carbonizing or activating carbon nanofibers, or both carbonizing and activating carbon nanofibers, using separate heating of nanofibers and process gases for increased sample temperature response to reduce production costs and improve process control. In one embodiment, the system includes a reactor tube into which a selected atmosphere can be introduced and which is closed at the ends by flanges. Samples are placed inside the tube on or in a susceptor, which is heated by RF induction via RF coils surrounding the reactor tube, and process gases, which can be independently heated, flow through the tube.
Agency: Department of Energy | Branch: | Program: STTR | Phase: Phase II | Award Amount: 750.00K | Year: 2010
The demands of the solar energy market require the development of advanced photovoltaic technologies. The DOE is seeking to develop organic PV technologies that are more efficient, long lasting and cost competitive to traditional ones. Organic PV (OPVs) have become well recognizedas an important candidate for future solar power products, although their efficiency is not exceeding 6-7%. The overall objective of this Phase II STTR project is the development and fabrication of tandem and multijunction OPVs with efficiency increased to the level of > 10-15 % which will open new markets for OPV, such as OPV power for portable devices: notebook PC, cell phones, outdoor solar lighting. A critical part of the proposed tandem OPV device operation is the transparent interconnecting layer, which allows the connection of sub-cell OPVs in a new parallel architecture. Carbon nanotube sheets of present program have been proven as interconnecting layers (called as
Agency: Department of Energy | Branch: | Program: STTR | Phase: Phase I | Award Amount: 149.00K | Year: 2010
This Small Business Technology Transfer Phase I project proposal focuses on attending to the need of photovoltaic power sources that can provide both high power and stability, be of low cost, low weight, flexible, and scalable to cover large areas. Organic photovoltaic (OPV) parallel tandem photovoltaic cells have a theoretical expected power conversion efficiency rivaling or even exceeding today
Solarno, Inc and The Board Of Regents Of The University Of Texas System | Date: 2012-01-24
The claimed invention uses activated carbon fibers that incorporate porous carbon with a suitable pore size to maximize capacitance. The porous carbon material is prepared using a template, followed by incorporation into a matrix polymer and electrospinning of the mixture. Subsequent thermal treatments retain the fiber form, and a composite carbon fiber incorporating templated porous carbon is attained. The resulting electrode is binder free and 100% electrochemically active. Energy densities up to 41 Wh/kg in energy density 1.5 kW/kg in power density (electrode weight only) have been achieved.
Solarno, Inc and The Board Of Regents Of The University Of Texas System | Date: 2011-06-07
A tandem (or multijunction) hybrid photovoltaic device (PV) device comprised of multiple stacked single PVs connected in parallel with each other is described herein. Furthermore, nanomaterials are used as transparent charge collecting electrodes that allow both parallel connection via anode interlayer and also inverted parallel connection via cathode type interlayer of different types of solar cells. Carbon nanotube sheets are used as a convenient example for the charge collecting electrodes. The development of these alternative interconnecting layers simplifies the process and may be also used for combined organic PVs with traditional inorganic PVs and Dye Sensitized Solar Cells (DSSC). In addition, novel architectures are enabled that allow the parallel connection of the stacked PVs into monolithic multi-junction PV tandems. This new monolithic parallel connection architecture enables enhanced absorption of the solar spectrum and results in increased power conversions efficiency. Moreover, architectures where cells are stacked monolithically using a series connection can be coupled with cells to create mixed series and parallel connected tandem cells.
Solarno, Inc and The Board Of Regents Of The University Of Texas System | Date: 2011-05-21
A tandem organic light emitting diode (OLED) device comprised of multiple stacked single OLEDs electrically connected in parallel via transparent interlayer is recited herein. Transparent interlayers are coated by charge injection layers in order to enhance the charge injection efficiency and decrease the operation voltage. Transparent nanomaterials, such as carbon nanotube sheets (or graphene, graphene ribbons and similar conductive transparent nano-carbon forms) are used as Interlayers or outer electrodes. Furthermore, functionalization of carbon nanotubes inter layers by n-doping (or p-doping) converts them into common cathode (or common anode), further decreasing operation voltage of tandem. The development of these alternative interconnecting layers comprised of nanomaterials simplifies the process and may be combined with traditional OLED devices. In addition, novel architectures are enabled that allow the parallel connection of the stacked OLEDs into monolithic multi-junction OLED tandems.
Solarno, Inc and The Board Of Regents Of The University Of Texas System | Date: 2014-08-08
An objective of the invention is to design and develop an effective method to collect and store heat in a solar collector for delayed release. An embodiment of the invention is directed to an evacuated tube collector, where PCM is placed directly inside the void space of the collector tube, next to the heat pipe. The heat pipe is located with phase change material (PCM) in such a way that its thermal connection with the heat pipe can be switched ON to start heat transfer from PCM or OFF to keep latent heat stored in PCM for delayed usage. In additional, flow of heat exchange fluid through the manifold can enable release of stored heat of PCM to storage tank. Delayed release of accumulated heat in PCM enables added functionality of on-demand operation of SWH.
Solarno, Inc and The Board Of Regents Of The University Of Texas System | Date: 2014-03-15
The present invention provides a method for making a highly efficient and inexpensive solar selective coating. Coating consists of various carbon nanotube sheets composite layers, each performing a specific function by incorporating functional materials and components with proper structure. Joule heating of the described solar selective coating allows for efficient functionality even when solar energy is not available.