A major stumbling block for organic solar cells has been the fact that they’ve relied on glass coated with Indium Tin Oxide (ITO). ITO coated glass is used in all sorts of electronics products such as LCD displays, iPads and some organic LED (OLED) TVs and computer monitors. In organic solar cells, the ITO glass functions as a transparent electrode (the clear top portion of the solar cell) The problem with ITO coated glass is that it can be fragile and toxic, and it is becoming ever more expensive to produce. Recognizing the limitations of ITO, researchers at the University of Warwick in the UK have been investigating using gold as an alternative coating and, according to their recent statement, they’ve met with success.
Gold is no stranger to the world of electronics, as it has been used to plate the connection points of electronics cables for years. The fact that it doesn’t ever corrode is a huge plus and one of the compelling reasons to use it for something like an organic solar cell. The challenge that the university researchers faced has been with depositing a film of gold thin enough to be transparent without being too fragile and electrically resistive to be useful.
Now research led by Dr Ross Hatton and Professor Tim Jones in the University of Warwick ’s Department of Chemistry has developed a quick method for preparing robust, ultra-thin gold films on glass and they say the process can be scaled up for applications like solar cells. The ultra-thin film of gold that gets deposited on the glass apparently measures just 8 billionths of a meter thick. So, even though gold prices are at an all time high, the researchers say that the amount of gold needed to make an electrode plate one square meter in size costs about £4.5, or $7.35.
The researchers seem confident that their gold-coating process could be utilized across a broad range of applications. A gold coated iPad screen? Maybe. Right now, the researchers seem focused on refining their process to deposit thin films of gold onto plastic, a feat they maintain would lead to “the holy grail of truly flexible solar cells.”
For more detailed information, the full research paper entitled Ultrathin Transparent Au Electrodes for Organic Photovoltaics Fabricated Using a Mixed Mono-Molecular Nucleation Layer is published in Advanced Functional Materials.
EarthTechling wants your opinion! Take EarthTechling’s 3-minute reader survey and enter to win a $250 Amazon gift card. The 2011 survey closes on April 15, 2011.