NANO IN FUTURE SPACE MISSION

Nanotechnology will play an important role in future space missions. Nanosensors, dramatically improved high-performance materials, or highly efficient propulsion systems are but a few examples. Propulsion Technology, harden electronic components and radiation shielding are the areas where nanotechnology could make a major contribution to human space flight. According to NASA, the risks of exposure to space radiation are the most significant factor limiting humans’ ability to participate in long-duration space missions. Therefore a lot of research has been going on developing countermeasures to protect astronauts from those risks. To meet the needs for radiation protection as well as other requirements such as low weight and structural stability, spacecraft designers are looking for materials that help them develop multifunctional spacecraft hulls. Advanced nanomaterials such as the newly developed, isotopically enriched boron nanotubes could pave the path to future spacecraft with nanosensor-integrated hulls that provide effective radiation shielding as well as energy storage.

Actually space radiation is qualitatively different from the radiation human encounters on Earth. Once astronauts leave the Earth's protective magnetic field and atmosphere, they become exposed to ionizing radiation in the form of charged atomic particles traveling at close to the speed of light. Highly charged, high-energy particles pose the greatest risk to humans in space. A long-term exposure to this radiation can lead to DNA damage and cancer. One of the shielding materials under study is boron 10.

A stable isotope, 105B (Boron), having five protons and five neutrons, that makes up about 20% of natural boron is a good absorber of slow neutrons and is used as a radiation shield. It has also been used in numerous applications such as a dopant in the semiconductor industry. Boron compounds also play important roles as light structural materials, nontoxic insecticides and preservatives, and reagents for chemical synthesis.

Compared to Carbon Nanotubes, boron nanotubes have some better properties which make them more suitable for space industry. They are having high chemical stability, high resistance to oxidation at high temperatures and also they are stable wide band-gap semiconductors. Because of these properties, they can be used for applications at high temperatures or in corrosive environments such as batteries, fuel cells, super capacitors, high-speed machines as solid lubricant.

But the major problem is that large quantity production of pure boron nanotubes requires a large quantity of this material.

NANO HELPS TO REDUCE CORROSION

In a recent advancement by Air Office of Scientific Research, transparent coating have been developed that causes the water to roll off the surface which will in turn to protect Air Force system by preventing corrosion and reducing ice formation on optical systems and Aircraft.

NANO POWER: HOPE FOR THE RURAL HOMES

Now if you go to the country side and see the rooms enlightened, don't frown.Electrification of homes in rural areas would no more be a distant dream with the help of nanotechnology.

Jamshedpur-based Ekta Telecommunication and Systems is working on incorporating nanotechnology in the development of solar modules to provide electricity to all at an affordable rate. The advanced technology can be a boon for rural and urban homes. Increase in efficiency is another benefit of the technology.The technology, based on the use of a combination of solar cells to build a module and eventually a solar cell
would be developed with the use of thin polymer sheets. Electricity would be generated by placing the thin sheet on the rooftop and drawing solar the power for lighting up the entire house. “Solar electricity is the only answer to the power crisis in contemporary times.The adoption of nanotechnology would ensure that we can provide electricity to
people at prices lower than what the commercial power providers charge,” said Niraj Kumar Mishra, the chairman and managing director of Ekta Telecommunication and Systems. The company is also working on making the modules available at affordable prices. Ekta is also focussing on increasing the efficiency of the modules.The cost of the
modules would decrease to Rs 5 from the existing Rs 150 to Rs 250 per watt, said officials. The efficiency of the solar modules would go up to an average of 50 per cent from the present rate of 14 per cent.

BROKEN TEETH: DONT WORRY!

If you have a broken teeth, you may think that it is gone. But wait a minute! Nanotechnolgy helps you to recreate your teeth.

In a new development, scientists revealed recently that teeth broken could soon be regrown using an ultrasound machine half the size of a thumbnail. The process could take just 12 weeks. Ultrasound is already used to help heal broken bones, now the technology is being applied to teeth. Nanotechnology, which can reduce electronic circuitry to one thousandth of the size of a human hair, has enabled scientists to develop an ultrasound device small enough to fit inside the mouth. A wafer-thin ultrasound chip, which is preprogrammed so that it turns on automatically, can be clipped onto the teeth. When it is on, ultrasound waves massage the gums to stimulate and increase blood flow to produce new tooth tissue.

Exploring Nanotechnology: Infants get a new light

An Indian microbiologist is trying to use nanotechnology to help identify an opportunistic pathogen that colonises recto-vaginal areas in up to 50 per cent of women worldwide and causes several life-threatening diseases in infants. Atul Kumar Johri, Associate Professor at JNU's School of Life Sciences in New Delhi, is keen to develop a mechanism to identify Group B Streptococcus (GBS) bacteria that cause pneumonia, sepsis and meningitis in newborns and is responsible for significant morbidity in pregnant women and the elderly.

Dr. Johri along with scientists from the Queensland Institute of Medical Research in Australia is working on a project to make use of nanotechnology for rapid, more sensitive as well as efficient detection of the GBS bacteria in pregnant women.

In the U.S., the UK and France, there is a mandatory test for detection of GBS in pregnant women between 35-37 weeks of their pregnancy. If the bacteria are detected in their samples, four hours before the birth of the child penicillin shots are given to the women through intravenous injections so that they can prevent the bacteria from infecting the baby and causing pneumonia and meningitis.

In India, there is no such test or even much knowledge about the existence and prevention of GBS. The fact that a large number of childbirths in the country happen outside the health centres is another cause for worry.
“Timely detection of GBS can save a lot of babies in India. The problem is that in India, common people are not even aware of such a micro-organism, diseases that it causes, and that it is so easily preventable. GBS has nine serotypes. In India, Type I-A and Type III are predominant. After they made the test mandatory, the number of children getting infected with such diseases in the Western countries has come down significantly,” informs Dr. Johri. He is also working with the Australian researchers to develop one universal vaccine for the GBS.

SUPERSONIC ELECTRIC AIRCRAFT

Commercial aviation is an essential component of the global economy. The cost of aviation fuel is directly determined by the prevailing world price of oil. It accounts for a major proportion of airplane operating costs. Several airline companies now add a fuel surcharge to the ticket cost of a commercial flight to compensate for the recent rapid rise in fuel costs. World oil prices are expected to remain high for several years. The prospect of sustained high aviation fuel prices could propel airline companies to seek alternative aviation fuels. Seeking alternative fuel could become become paramount for the airline industry should the peak-oil phenomena actually occur. The commercial aviation industry would likely compete for fuel and energy in a market of scarcity and escalating fuel prices.

Breakthroughs and Research

It may become possible for supercooled liquid hydrogen to eventually be used as an alternative fuel for some types of commercial airline service. Extensive research will be needed to resolve the numerous logistical problems that are related to its use as an alternative aviation fuel in supersonic and hypersonic aircraft. Other alternative fuels may include high-density energy-storage technologies that result from breakthroughs in research in the areas of nanotechnology and in high-temperature superconductivity.

Sporadic and significant breakthroughs periodically occur in both fields. High-temperature superconductivity holds great promise for use in high-density energy-storage technology. A coil formed into a torus and made from "high-temperature" superconductive material could theoretically store enough energy to enable a full-sized commercial airliner to undertake an extended trans-oceanic or trans-continental flight. Advances in nanotechnology could enable superconductive materials to eventually be manufactured at a cost that could justify their application in airliner propulsion.

Electrical Storage and Propulsion

Energy stored in a superconductive storage technology could power electric motors that drive the identical propulsion fans that are found at the front-end of modern, "high-bypass" turbo-fan aircraft engines. Such fans provide up to 90% of the propulsive thrust of the turbo-fan engine. Each electrically powered propulsion fan may be driven by multiple (induction) lightweight electric motors during take-off. Some electric motors would "cut-out" under reduced power demand at cruising altitude so that the remaining motors will operate at higher efficiency (electric motors have poor part-load effciency).

Coanda fans may propel subsonic commercial aircraft that use high-density electrical storage technology. Such units were originally developed by physicist Henri Coanda and can operate at comparable efficiency and at comparable flight speeds as turbine-driven propulsion fans. Electrically powered aircraft that use either turbine propulsion fans or Coanda fans could be flown in thinner air at higher altitude (up to 65,000-feet) to reduce energy consumption (less drag on aircraft) on extended flights. The cooler air found at such altitudes could assist in keeping the superconductive energy storage systems functioning properly.

Superconductive energy storage systems used in future commercial aircraft would likely be cooled by liquid nitrogen. Both systems would need to be frequently recharged. Commercial aircraft that operate long-haul service usually undergo cleaning and servicing in hangars after long flights. It is during such service periods when the energy storage and cooling systems could be recharged, a process that would likely be both energy-intensive as well as time consuming.

It may be possible to design the energy storage systems along with their cooling systems to be removed and replaceable during shorts layovers. Such technology may be possible and could help reduce the turn-around time of the aircraft. The introduction of superconductive energy storage systems in commercial aircraft in the long-term future would require that future airport terminals be equipt with power generation technology at or near the premises.

Short-haul/Commuter Aircraft

Aircraft turbine engines are very flexible in the kind of fuel that they can burn. Short-haul and commuter airline companies that operate routes of under 500-miles would be the most likely candidates to use alternative aviation fuel. Their fleets are mainly powered by turbo-prop or by turbofan engines and may likely have sufficient capacity in the fuel tanks to carry a cheaper fuel with a lower energy content. They may use such fuel if its cost per BTU undersells fossil aviation fuel. Breakthroughs in electrical storage technology could see a future generation of short-haul and commuter aircraft being propelled by electric motors driving propellers or propulsion fans.

Low-Altitude Flight

Ground-effect aircraft use a specialized wing design that generated a cushion of air between the wing and the surface over which it flies. Large and heavy versions of such aircraft could be flown at moderate speed over water and carry passengers and freight between coastal centres of up to 500-miles apart. Eliminating the need for take-off to at least 10,000-feet would cut fuel costs. The performance of such craft can be enhanced by a recent development from Britain that has been successfully tested in a scale model aircraft.

Aeronautical "paddle wheels" are mounted transversely on the topside of aircraft wings to provide propulsion and increase lift at very low flight speeds. Such craft may to be propelled by electrically driven propellers that are the size of helicopter rotors. Such units can move a large mass of air at lower velocity to deliver high thrust (200,000-lbf per propeller) at higher propulsive efficiency. An alternative system could see heated air being ducted through the thick rotor blades to adjustable jets that are built into the tips of the rotors.

Low Speed (Electrically-powered) Supersonic Flight

An American company called Supersonic Aerospace International (SAI) recently undertook research into reducing the sonic boom of supersonic commercial flight. The result was a unique configuration of supersonic aircraft capable of flying quietly at Mach 1.5. It is theoretically possible to develope an electrically powered engine capable of propelling a commercial aircraft to such a flight speed.

A high-temperature superconductive energy storage system would supply power to 2-sets of electric motors that drive different propulsion systems. A subsonic propulsion system of electrically driven propellers would accelerate the aircraft up to a flight speed of Mach 0.5 when the supersonic engines would engage. These engine would have a cross sectional profile similiar to that of a ramjet.

The electric motor and compressor would be housed in a straight tube intake pipe that would be flowed by a section of gently increasing diameter. A shock wave at the entrance of the pipe would see air speed drop from Mach 1.5 to Mach 0.7. The air temperature would rise from minus 40-degrees F to 95-degrees F. An electrically driven axial flow (single spool) compressor operating at 93% isentropic efficiency and having a pressure ratio of 8 to 1 would further increase air temperature to 580-degrees F.

The heated air would flow into the diffuser (where area quadruples) where air pressure would increase by up to 25% and air temperature would rise to 648-degrees F at the maximum cross section. Air would then flow into a nozzle (smaller cross section) at sonic speed and accelerate into a diverging exhaust section where air would leave at over 2534-feet per second (Mach 1.5 at -40-degrees F is 1507-feet per second). The engine would move a very large volume of air to provide sufficient thrust to maintain flight speed. A pressure ratio of 10:1 on the compressor could raise the exit velocity of the air to 2704-feet per second.

Faster Supersonic Flight

The electrically powered engine that could theoretically propel an aircraft to a flight speed of Mach 1.5 could be modified to operate at higher speed. The engine intake would be modified to an "Oswatitsch" design with variable geometry. That design would generate (weaker) oblique shock waves at the entrance to the engine as well as be able to "dump" excess air or duct in extra air depending on flight conditions.

The faster engine may use a single-spool axial flow compressor that has more pressure ratio (up to 15 to 1 with variable stator blades) to raise air temperature. The aircraft may carry water in special tanks and electrolysis gear to generate hydrogen that may be injected ahead of the nozzle of the engine. The combustion of the hydrogen would increase the air temperature and raise the exit velocity of the gas that leaves the engine. Flight speeds of Mach 2 to Mach 2.4 may be possible.

Power Generation

The number of electrically powered and hydrogen powered road and railway vehicles would likely increase during a post peak-oil period. Commuter aircraft that operate short-haul service could be powered by ethanol or by hydrogen while future supersonic aircraft could use liquid hydrogen as fuel. The commercial aviation industry of the future (post peak oil) could likely require vast amounts of electric power to recharge superconductive energy storage systems, recharge liquid nitrogen cooling systems as well as to generate, compress and supercool large amounts of hydrogen.

Modern commercial aircraft are energy intensive during take-off. Airports that serve metropolitan areas presently process continual processions of large long-distance aircraft during peak periods. Such aircraft could require between 300-Mw-hr and 1000-Mw-hr of power to undertake trans-oceanic flights at subsonic speed. The power requirements of a future electrically based commercial aviation industry could likely overwhelm the power generation industry of most developed nations.

Major international airports may eventually need to generate electric power on-site to meet the energy needs of future fleets of electrically powered and hydrogen-fueled commercial aircraft. Airport power stations may be nuclear; use hydrogen fusion or be based some other unconventional power generation technology that is still subject to research. The heat that will be rejected by these thermal power stations could be reclaimed and put to productive use that would would include:

* Heating buildings (district heating) during winter.

* Putting heat into geothermal storage during summer for use during.

* Powering absorption air-conditioning systems during summer.

* Energising low-grade heat engines to generate electricity during winter.

Energy Storage

The ability to store large amounts of energy at or near major airports could gain importance during a post peak-oil period. Electric power could be purchased from the grid during their off-peak periods and put into short-term storage. Airport power stations that encounter off-peak periods could replenish airport energy storage systems that may include superconductive storage, flow batteries, hydraulic storage in hydroelectric dams in nearby mountains (coastal airports) or off-site pneumatic storage (subterranean salt domes that were emptied). Air that is exhausted from pneumatic storage systems may be sufficiently cold to assist in "replenishing" liquid nitrogen supercooling systems.

Power Regulation (Airports)

Power stations that provide energy for air transportation use may have to be excluded from the regulatory framework. Most of the electrically powered airliners that will be recharged would be "foreign" owned, that is, the owners would be domiciled in a different jurisdiction to where the aircraft would be recharged. The idea of regulators in one jurisdiction looking after the interests of parties who live, do business and pay taxes in another jurisdiction is quite ludicrous. Power stations that supply a future airline industry with electric power would need to be regulatory-free despite the "foreign" airline owners being "captive" customers. It would be possible for power to be supplied to a single airport by several small providers who compete against each other. Power providers and airline companies could negotiate deals including on a daily basis.

Conclusions

Future scientific breakthroughs are likely to occur in both nanotechnology and in superconductivity. High-density energy storage technologies could be the likely result and appear in the distant future. Electrically powered commercial aircraft that fly at subsonic speeds could appear in the future irrespective of whether or not peak-oil actually occurs. Alternative liquid fuels that are cost-competitive to fossil oil are also likely to appear and find application in aviation. Large ground-effect aircraft that fly above water and that carry either passengers or freight between coastal cities are also likely appear in the future.

VIRUS: Nano particle Memory Booster

A new type of digital memory device has been created by incorporating inorganic platinum nanoparticles into the tobacco mosaic virus (TMV).

The work was done by researchers at the University of California, Los Angeles (UCLA), who claim that the result could find application in the development of bio-compatible electronics.

In recent years researchers have exploited the unique selectivity of biomaterials by nanostructuring biological molecules with inorganic materials for applications such as biosensing. The UCLA researchers have taken this idea one-step further with a hybrid biological system that can store digital information.

“We have developed an electronic device, fabricated from the tobacco mosaic virus conjugated with nanoparticles, which exhibits a unique memory effect,” Yang Yang, the group’s lead researcher at the University of California, told physicsweb.org. “This device can be operated as an electrically bistable memory device whose conductance states can be controlled by a bias voltage. The states are non-volatile and can be digitally recognized.”

The TMV is a 300 nm tube consisting of a protein capsid (outer shell) and RNA core. According to the researchers, the TMV’s thin, wire-like structure makes it suitable for attaching nanoparticles. In this case, it allowed them to add an average of sixteen positive platinum ions per virion. The device works by transferring charge, under a high electric field, from the RNA to the Platinum nanoparticles with the TMV’s surface proteins acting as an energy barrier, stabilising the trapped charges.

“The TMV’s surface makes it an ideal template for organizing the nanoparticles, which can bind to the specific carboxyl or hydroxyl sites on the surface,” said Yang. “The RNA core in TMV is likely to serve as the charge donor to the nanoparticles with the coat proteins acting as the barrier to the charge transferring process.”

The TMV hybrid, says the team, has an access time ( the delay between a call for storing data and for data storing to begin) in the microsecond regime. This is comparable to today’s flash memory. In addition, the device is non-volatile, which means that data is retained once the computer’s power is turned off.

The researchers say the device still needs to be scaled-down to a smaller size to increase storage density and to include more circuitry. “There will be issues involving retention time, power consumption, and integration of drivers required to write and read each bit, which we need to consider in order to optimize the system,” said Yang.

In the long term, these devices could one day be integrated in biological tissues for applications in therapeutics or biocompatible electronics.

SILICON QUANTUM COMPUTER

Keio university researchers are working on a project to produce a revolutionary quantum computer using 'silicon', the same material as present classical computers, which can work as a bridge between classical and quantum mechanics. The quantum computer based on silicon is designed and developed. Present computers work on the basis of the law of the classical mechanics that Newton and Maxwell established. On the other hand, a computer operating with the absolutely new concept based on the law of the quantum mechanics that Einstein et al. found in the 20th century is a quantum computer. Its implementation requires not just understanding of the quantum mechanics from its basics but also knowledge and technology to integrate creatively mathematical computer science and nanotechnology at an atomic level.

NANO MAGIC: HYDROGEN WITHOUT CARBON

Craig A. Grimes, a professor of electrical engineering and Director of Centre of Nano Science and Technology and his team are working towards a cost effective way to produce hydrogen, previously what has been done with a very cost. They are also working on the carbon less hydrogen production.

Currently, the steam reforming of natural gas produces most of the hydrogen. As a fuel source, this produces two problems. The process uses natural gas and so does not reduce reliance on fossil fuels; and, because one byproduct is carbon dioxide, the process contributes to the carbon dioxide in the atmosphere, the carbon footprint.

Grimes' process splits water into its two components, hydrogen and oxygen, and collects the products separately using commonly available titanium and copper. Splitting water for hydrogen production is an old and proven method, but in its conventional form, it requires previously generated electricity. Photolysis of water solar splitting of water has also been explored, but is not a commercial method yet.

Grimes and his team produce hydrogen from solar energy, using two different groups of nanotubes in a photo electrochemical diode. This method generates photocurrent of approximately 0.25 milliampere per centimeter square, at a photo conversion efficiency of 0.30 percent.

"It seems that nanotube geometry is the best geometry for production of hydrogen from photolysis of water," says Grimes.

In Grimes' photo electrochemical diode, one side is a nanotube array of electron donor material - n-type material - titanium dioxide, and the other is a nanotube array that has holes that accept electrons - p-type material - cuprous oxide titanium dioxide mixture. P and n-type materials are common in the semiconductor industry. Grimes has been making n-type nanotube arrays from titanium by sputtering titanium onto a surface, anodizing the titanium with electricity to form titanium dioxide and then annealing the material to form the nanotubes used in other solar applications. He makes the cuprous oxide titanium dioxide nanotube array in the same way and can alter the proportions of each metal.

While titanium dioxide is very absorbing in the ultraviolet portion of the sun's spectrum, many p-type materials are unstable in sunlight and damaged by ultraviolet light, they photo-corrode. To solve this problem, the researchers made the titanium dioxide side of the diode transparent to visible light by adding iron and exposed this side of the diode to natural sunlight. The titanium dioxide nanotubes soak up the ultraviolet between 300 and 400 nanometers. The light then passes to the copper titanium side of the diode where visible light from 400 to 885 nanometers is used, covering the light spectrum.

The photo electrochemical diodes function the same way that green leaves do, only not quite as well. They convert the energy from the sun into electrical energy that then breaks up water molecules. The titanium dioxide side of the diode produces oxygen and the copper titanium side produces hydrogen.

Although 0.30 percent efficiency is low, Grimes notes that this is just a first go and that the device can be readily optimized.

"These devices are inexpensive and because they are photo-stable could last for years," says Grimes. "I believe that efficiencies of 5 to 10 percent are reasonable.

SECRETS OF NANO WORLD: REVEAL BY SUPER X RAY MICROSCOPE

Researchers have been working on such super-resolution microscopy concepts for electrons and x-rays for many years. A novel super-resolution X-ray microscope developed by a team of researchers from Paul Scherrer Institute (PSI) and EPFL (ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE). They combine the high penetration power of x-rays with high spatial resolution, thereby creating possibility to shed light on the detailed interior composition of semiconductor devices and cellular structures.

The new instrument uses a Megapixel Pilatus detector which has excited the synchrotron community for its ability to count millions of single x-ray photons over a large area. This key feature makes it possible to record detailed diffraction patterns while the sample is raster-scanned through the focal spot of the beam. In contrast, conventional x-ray (or electron) scanning microscopes measure only the total transmitted intensity.

These diffraction data are then treated with an algorithm. An image reconstruction algorithm was developed that deals with the several tens of thousands of diffraction images and combines them into one super-resolution x-ray micrograph explains PSI researcher Pierre Thibault, first author on the publication. Even in order to achieve images of the highest precision, the algorithm not only reconstructs the sample but also the exact shape of the light probe resulting from the x-ray beam.

Conventional electron scanning microscopes can provide high-resolution images, but usually only for the surface of the specimen, and the samples must be kept in vacuum. The Swiss team's new super-resolution microscope bypasses these requirements, meaning that scientists will now be able to look deeply into semiconductors or biological samples without altering them. It can be used to non-destructively characterize nanometer defects in buried semiconductor devices and to help improve the production and performance of future semiconductor devices with sub-hundred-nanometer features. A further very promising application of the technique is in high-resolution life science microscopy, where the penetration power of X-rays can be used to investigate embedded cells or sub-cellular structures. Finally, the approach can also be transferred to electron or visible laser light, and help in the design of new and better light and electron microscopes.

HISTORY OF NANOTECHNOLOGY

(1) The first use of the concepts in 'nano-technology' was in "There's Plenty of Room at the Bottom," a talk given by physicist Richard Feynman at an American Physical Society meeting at Caltech on December 29, 1959. He described a process by which the ability to manipulate individual atoms and molecules might be developed.


(2) In the course of this, he noted, scaling issues would arise from the changing magnitude of various physical phenomena: gravity, surface tension and Van der Waals attraction.

(3) In the year of 1965, in a breakthrough observation by Gordon Moore, it was noticed that silicon transistors were undergoing a continual process of scaling downward. This was famously known as Moore’s Law.





(1) Then in the year of 1974 the term “NANO-TECHNOLGY” comes. It was defined by Tokyo Science University Professor Norio Taniguchi. In his paper he defined it as: "'Nano-technology' mainly consists of the processing of, separation, consolidation, and deformation of materials by one atom or by one molecule."
(2) Also in 1974, one atom thick deposition technique was developed patented by Dr. Tuomo Suntola and co-workers in Finland.

(3) Thereafter, Dr. K. Eric Drexler an American engineer promoted the technological significance of nano-scale phenomena in the 1980’s. He actually conceptually explored the idea of handling the individual atoms and molecules. Drexler's vision of nanotechnology is often called "Molecular Nanotechnology" (MNT) or "molecular manufacturing," and Drexler at one point proposed the term "zettatech" which never became popular.

NANO SOLAR ENERGY

Northwestern chemistry professor Mark Ratner hopes that one day energy crisis can be solved with the help of blue jean dye and white house paint.The technology would use tiny nanostructures to convert sunlight into energy, similarly to the process of photosynthesis in plants.It's just one application of nanotechnology to the energy problem.

THE PROBLEM:


With oil prices topping $140 a barrel this week, and recent studies suggesting ethanol and other plant-based fuels may be worse for the environment than conventional fuels, pressure is growing to find a better solution. Wind and geothermal power can provide clean energy, but not enough of it. For a solution to be truly effective, it must be scalable. That is, it must produce enough energy to meet the world's needs - especially considering the rapid growth of countries like India and China.


A NEW KIND OF SOLAR PANEL:
Scientists are now trying to design solar panels using nanostructures that work like leaves, but better. The goal is 30 percent efficiency in converting sunlight into power - much higher than the efficiency of biofuels. While conventional solar panels made from silicon are about 18 percent efficient, the cost involved in making them is so high.Nanostructures, on the other hand, would use inexpensive materials to capture sunlight. That's where the blue jeans and house paint come in.



In artificial photosynthesis, you need a molecule to absorb the sunlight, but not any molecule will do. The molecules that we probably want to use are related to the blue jean dye that you've got," Ratner said. It's a planar molecule, it has the right shape and it has the right energy properties.

The dye is called a thalocyanine and is also found in shoe polish.

Once the molecules capture solar energy, that energy must be stored somewhere - otherwise, it will be given off as heat. White house paint contains titanium dioxide, and when mixed with the dye molecules, titanium dioxide holds on to the energy the dye collects.