Infrared Plastic Solar Cell Abstract of Infrared Plastic Solar Cell Nanotechnology is the nexus of sciences. Nanotechnology is the engineering of tiny machines - the projected ability to build things from the bottom up using techniques and tools being developed today to make complete, highly advanced products. It includes anything smaller than 1 nanometers !ith novel properties. "s the pool of available resources is being exhausted, the demand for resources that are everlasting and eco-friendly is increasing day by day. #ne such form is the solar energy. $he advent of solar energy just about solved all the problems. "s such solar energy is very useful. %ut the conventional solar cells that are used to harness ha rness solar energy are less e&cient and cannot function properly on a cloudy day. day. $he use of nanotechnology in the solar cells created an opportunity to overcome this problem, thereby increasing the e&ciency. $his paper deals !ith an o'shoot in the advancement of nanotechnology, its implementation implementation in solar cells and its advantage over the conventional commercial commercial solar cell. In order to the miniaturi(ation of integrated circuits !ell into the present century, it is likely that present day, nano-scale or nano electronic electronic device designs !ill be replaced !ith ne! designs for devices that take advantage of the quantum mechanical e'ects that dominate on the much smaller ,nanometer scale . Nanotechnology is often referred referred to as general purpose technology. technology. $hat is because in its mature form it !ill have signi)cant impact on almost all a ll industries and all areas of society. society. It o'ers better built, longer lasting, cleaner, safer and smarter products for the home, for ammunition,
for medicine and for industries for ages. $hese properties of nanotechnology have been made use of in solar cells. *olar energy is really an abundant source that is rene!able and pollution free. $his form of energy has very !ide applications ranging from small household items, calculators to larger things like t!o !heelers, cars etc. they make use of solar cell that coverts the energy from the sun into required form.
Working Of Conventional Solar Cell %asically conventional type solar cells +hotovoltaic + cells are made of special materials called semiconductors such as silicon, !hich is currently the most commonly used. %asically, !hen light strikes the cell, a certain portion of it is absorbed !ithin the semiconductor material. $his means that the energy of the absorbed light is transferred to the semiconductor. $he energy knocks electrons loose, allo!ing them to /o! freely. + cells also all have one or more electric )elds that act to force electrons freed by light absorption to /o! in a certain direction. $his /o! of electrons is a current, and by placing metal contacts on the top and bottom of the + cell, !e can dra! that current o' to use externally. 0or example, the current can po!er a calculator. $his current, together !ith the cells voltage !hich is a result of its built-in electric )eld or )elds, de)nes the po!er or !attage that the solar cell can produce. 2onventional semiconductor solar cells are made by polycrystalline silicon or in the case of highest e&ciency ones crystalline gallium arsenide. %ut by this type of solar cell, it is observed that, only 345 of the suns total energy falling on it could be judiciously used. "lso, this is not so favorable on cloudy days, thus creating a problem. $his major dra!back led to the thought of development of a ne! type of solar cell embedded !ith nanotechnology. $he process involved in this is almost the same as explained earlier. %ut the basic di'erence lies in the absorption of the !avelength of light from the sun.
Infrared Plastic Solar Cell *cientists have invented a plastic solar cell that can turn the suns po!er into electric energy even on a cloudy day. +lastic solar cells are not ne! .%ut existing materials are only able to harness the sun6s visible light. 7hile half of the sun6s po!er lies in the visible spectrum, the other half lies in the infrared spectrum. $he ne! material is )rst plastic compound that is able to harness infrared portion. 8very !arm body emits heat. $his heat is emitted even by man and by animals, even !hen it is dark outside. $he plastic material uses nanotechnology and contains the 1stgeneration solar cells that can harness the sun6s invisible infrared rays. $his breakthrough made us to believe that plastic solar cells could one day become more e&cient than the current solar cell. $he researchers combined specially designed nano particles called quantum dots !ith a polymer to make the plastic that can detect energy in the infrared. 7ith further advances the ne! +9"*$I2 *#9": 2899 could allo! up to 35 of sun6s radiant energy to be harnessed completely !hen compared to only ;5 in today plastic best plastic solar cells. " large amount of sun6s energy could be harnessed through solar farms and used to po!er all our energy needs. $his could potentially displace other source of electrical production that produce green house gases like coal. *olar energy reaching the earth is 1 times than !hat !e consume. If !e could cover .15 of the earth6s surface !ith the solar farms !e could replace all our energy habits !ith a source of po!er !hich is clear and rene!able. $he )rst crude solar cells have achieved e&ciencies of today6s standard commercial photovoltaic6s the best solar cell, !hich are very expensive semiconductor laminates convert at most, 345 of the sun6s energy into electricity.
Working of Plastic Solar Cell $he solar cell created is actually a hybrid, comprised of tiny nanorods dispersed in an organic polymer or plastic. " layer only < nanometers thick is sand!iched bet!een electrodes and can produce at present about .= volts. $he electrode layers and nanorods >polymer layers could be applied in separate coats, making production fairly easy. "nd unlike todays semiconductor-based photovoltaic devices, plastic solar cells can be manufactured in solution in a beaker !ithout the need for clean rooms or vacuum chambers. $he technology takes advantage of recent advances in nanotechnology speci)cally the production of nanocrystals and nanorods. $hese are chemically pure clusters of 1 to 1 atoms !ith dimensions of the order of a nanometer, or a billionth of a meter. %ecause of their small si(e, they exhibit unusual and interesting properties governed by quantum mechanics, such as the absorption of di'erent colors of light depending upon their si(e. Nanorods !ere made of a reliable si(e out of cadmium selenide, a semi conducting material. Nanorods are manufactured in a beaker containing cadmium selenide, aiming for rods of diameter-= nanometers to absorb as much sunlight as possible. $he length of the nanorods may be approximately ;nanometers.$hen the nanorods are mixed !ith a plastic semiconductor called p3ht-poly-3-hexylthiophene a transparent electrode is coated !ith the mixture. $he thickness, < nanometers-a thousandth the thickness of a human hair-is a factor of 1 less than the micron-thickness of semiconductor solar cells. "n aluminium coating acting as the back electrode completed the device. $he nanorods act like !ires. 7hen they absorb light of a speci)c !avelength, they generate an electron plus an electron hole-a vacancy in the crystal that moves around just like an electron. $he electron travels the length of the rod until it is collected by aluminium electrode. $he hole is
transferred to the plastic, !hich is kno!n as a hole-carrier, and conveyed to the electrode, creating a current.
Improvements *ome of the obvious improvements include better light collection and concentration, !hich already are employed in commercial solar cells. *igni)cant improvements can be made in the plastic, nanorods mix, too, ideally packing the nanorods closer together, perpendicular to the electrodes, using minimal polymer, or even none-the nanorods !ould transfer their electrons more directly to the electrode. In their )rstgeneration solar cells, the nanorods are jumbled up in the polymer, leading to losses of current via electron-hole recombination and thus lo!er e&ciency. $hey also hope to tune the nanorods to absorb di'erent colors to span the spectrum of sunlight. "n eventual solar cell has three layers each made of nanorods that absorb at di'erent !avelength
Conclusion and Future Scope +lastic solar cells help in exploiting the infrared radiation from the suns rays. $hey are more e'ective !hen compared to the conventional solar cell. $he major advantage they enjoy is that they can even !ork on cloudy days, !hich is not possible in the former. $hey are more compact and less bulky. $hough at present, cost is a major dra!back, it is bound be solved in the near future as scientists are !orking in that direction. "s explained earlier, if the solar farms can become a reality, it could possibly solve the planets problem of depending too much on the fossil fuels, !ithout a chance of even polluting the environment.
References 1. Nanomaterials? *ynthesis, +roperties and "pplications ? 8delstein, ". *., 2ammarata, :. 2., 8ds.@ Institute of +hysics +ublishing? %ristol and +hiladelphia, 1AA;. <. $he 2oming 8ra of Nanotechnology @ 1AB=. Crexler, D. 8ric, Coubleday@ Ne! Eork 3. " gentle introduction to the next big idea-Fark ". :atner, Caniel :atner. G. Introduction to nanotechnology- 2harles + +oole, 0rank H #!ens 4. $he clean po!er revolution- $roy elming
