Artificial Leaf: Tata’s Investment In Sun Catalytix Opens New Avenues

World’s cheapest water purifier, “Swach”, people’s car: “Nano”, and a legacy of more than hundred years to prove the maxim “Been there, done that”. This is what defines TATA, the great Indian conglomerate. You name a product in any field and it would be difficult not to find Tata’s footprints there. Living up to its tradition, Tata has added another feather to its cap by investing into Sun Catalytix, a start up consisting of scientists from the esteemed MIT. What prompted Tata to pour about $9.5 million along with Sun Catalytix's current investor, venture capital firm Polaris Ventures? The reason is pretty simple and obvious. Tata is looking forward in strengthening their foothold in the field of non conventional energy sources. And they are doing it very aggressively. People at Sun #-Link-Snipped-#Catalytix have designed a device which they say replicates the natural process of photosynthesis in a smart and efficient way. #-Link-Snipped-#, has developed a device which enables the splitting of hydrogen and oxygen from the water with the help of solar energy. The device looks just like #-Link-Snipped-#, a commercial solar panel combined with cheap catalysts, and is the product of thin film technology used to develop solar panels. The catalyst comprises of cobalt and nickel and is capable of splitting water into its constituents with relative ease. Nocera built a solar panel which can produce hydrogen sufficient to supply a home with electricity 24 hours. A panel having an area of about one square meter can lighten up homes in a developing country like India.

Great efforts from Nocera were spent in developing this device. He had initially developed catalyst consisting of cobalt which could split oxygen from water in 2008. The problem he faced was that the catalyst could not be directly linked with silicon. By doing so, sunlight was blocked and the process of photosynthesis could not be carried out. Nocera did not get disheartened but continued in his quest by applying a thin layer on top of silicon. This reduced the blocking of incident sunlight to as low as 2 to 3 %. The silicon was coated with a thin membrane before the application of the catalyst. This feature protects the silicon from undergoing oxidation whereas the electricity is allowed to pass through the membrane.

He has also developed a nickel based catalyst which helps in extraction of hydrogen from water. This catalyst is applied to the other side of silicon. This technique of using nickel base catalyst is not 100% novel but has been used in various water splitting electrolyzers. But Nocera and his team have developed a technique which saves the nickel catalysts to get affected by phosphate and borate present in water. The results have been amazing and the outcome is a product which can operate for about six days with a constant efficiency. The natural process of photosynthesis results into the conversion of sunlight into useful energy with an efficiency of 1%. Nocera claims that they have achieved an efficiency of about 7%. They have also reached figures of 5% efficiency in getting hydrogen from water with the help of sunlight. I have already explained a similar process which separates the constituents of water in “#-Link-Snipped-#” . So what does the firm Sun Catalytix offer new? They have used cheaper metal catalyst to split water into hydrogen and oxygen. Further, it does not require a separate device but the process is performed by the artificial leaf itself. So the use of virtually transparent cobalt catalyst is what sets Nocera and his team’s achievement apart, according to John Turner, a research fellow at the National Renewable Energy Laboratory in Golden, Colorado.

After getting funds from the TATA group, Sun Catalytix plans to bring a commercially viable product by this year end. The first prototype will be based on a 100 watt solar panel. It is going to need a separate electrolyzer wired to the panels. The proposed cost is around $100 and it will have to co-ordinate with a fuel cell to transform stored hydrogen to electricity. Let us expect TATA and Sun Catalytix to deliver another gem.

News Credit: CNET: Product reviews, advice, how-tos and the latest news | #-Link-Snipped-# Image credit: CNET: Product reviews, advice, how-tos and the latest news