Google Science Fair

Deepika Kurup - Photocatalic approach to purify water

A world changing invention crafted by a mere teenager has the potential to trigger a drastic change in the amount of people affected by drinking impure water. 

Deepika Kurup was inspired to solve the water crisis during her visits to India. She saw some students drinking impure water from a nearby creek. She was troubled and set ambition to change this situation. Her research proves that currently, many countries are using the SODIS process. Clear plastic bottles are filled with contaminated water, and are exposed to the sun for about 8 hours. This disrupts the DNA of any harmful bacteria or germs. This is a very useful, and cost effective method, however consumes a large amount of time.

Recently, photocatalyst, such as titanium dioxide has been used to accelerate the cleaning process. A film of titanium dioxide is added on the inner side of these clear bottles. But even this process has a problem. When exposed to sunlight, this layer of titanium dioxide mixes into the water , thus making this process ineffective.

Deepika has invented a novel way to filter the toxins out of the water using a pervious composite mixture of titanium dioxide and silver. She created seven filters with different amounts of silver. (The last sample was her control sample with no titanium dioxide and silver. She then took these filters and placed methylene blue on top. She discovered that the combination of 3.85 % of titanium dioxide and 0.04 of silver (Ag) is the fastest in changing methylene blue to clear. (Her filter disrupts the harmful chemicals in methylene blue).

In her next experiment, she took sample number four and 7 (control) and passed impure water through both of them. She took the samples and set them in the sun. Her experiment proved that her filter is more effective and less time consuming than the simple photocatalytic and SODIS process.

I believe that Deepika can win the Google Science Fair because she has taken a worldwide crisis, and has come up with an effective, and less time consuming way to solve the problem. Water is a necessary element needed for human survival. For this reason, we need a pure source of it. This method can quench a large amount of people’s thirst and save thousands of lives. It can also prevent people catching diseases by consuming impure water.