Now Transparent Electrodes For Organic Solar Cells Made From Gold

Warwick University scientists have devised a technology to manufacture transparent electrodes using pure gold. These transparent electrodes will be used in organic solar cells and other optoelectronic devices. Most of you might be wondering about the economical feasibility electrodes made out of gold. However, unlike the common belief, the manufacturing and processing costs are pretty less. The electrodes are so cheap because the gold layer used is as thin as 8 billionth fraction of 1 meter. This ultra thin layer of gold implies that though the current rate of gold is sky high, the actual cost incurred for fabrication of a square meter of the transparent golden electrode comes out to be approximately £4.50 only. Also, this gold can be extracted back from an organic solar cell after it stops working. So the economic factor is not a problem for this technology.

#-Link-Snipped-#So after checking the viability of this out-of-the-box idea with reference to cost, we should ask the question that why this golden window electrode is better than the currently used electrode? For answering this query, we should first acquaint ourselves with the contemporary electrodes and their drawbacks. Till date, the organic solar cells have been using Indium Tin Oxide (ITO) coated glass for making the transparent electrodes. The problem with the ITO is that it is having a complex chemical composition of highly unstable nature. Also, its surface is rough and very uneven. As a result, the glass tends to crack when bent on a plastic substrate. In addition, the main component Indium is not so abundantly available and is always facing supply shortage leading to escalated prices. The only reason behind the usage of ITO is the lack of substitute materials. With the arrival of the gold electrodes, their usage is surely going to diminish.

Dr Ross Hatton and Professor Tim Jones in the University of Warwick’s department of Chemistry have come up with a brilliant technique for quick deposition of super thin, robust and electrically conducting film of gold on glass surface. Very large surface area glasses can be coated with transparent gold using this method thus making the process suitable for organic solar cells. The electrodes thus formed have a prominent and well defined chemical structure. Gold has the advantages that it is a very good conductor of electricity, it is highly ductile and malleable, it is a noble element so more stability in air and it has a smmoth surface unlike the ITO glass. Dr. Hatton believes that the golden window electrodes have great potential. They can be used as electrodes in many applications in the fields of organic optoelectronics, nanoelectronics and nanophotonics. This research was published in <em>Advanced Functional Materials </em>in the form of the paper titled “Ultrathin Transparent Au Electrodes for Organic Photovoltaics Fabricated Using a Mixed Mono-Molecular Nucleation Layer”. The paper gives a detailed report regarding the successful development of a practical and cost effective method for deposition of films on glass substrate. The paper also tells that the optical qualities of the material can be further enhanced by perforating the film with minute holes with the help of polystyrene balls. The team of Warwick researchers is now trying to deposit these transparent gold films on plastic substrate to achieve the ultimate goal of flexible solar cells. The Warwick University graduates have also found a startup called Molecular Solar Limited, so as to commercialize the various technological advances made by them and introducing these technologies to the entire world.

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