Imagine Magazine - Johns Hopkins - January/February 2013 - (Page 21)

Brought to You by Sunlight and Science have been passionate about solving the global water crisis ever since I was in elementary school. When on summer vacation in India, I witnessed children drinking contaminated water from a stagnant pool. As I grew older, I was astonished to learn that over two million people, most of them children in developing countries, die each year of water-related diseases. The Discovery Education 3M Young Scientist Challenge (YSC) gave me a way to do something about this problem. The 2012 YSC asked students to create a one- to two-minute video describing an innovation that would address an everyday problem related to the way we move, stay healthy, or make a difference. My video entry described my idea for harnessing solar energy to purify water. My idea was to use photocatalysis (accelerating a photoreaction by the presence of a catalyst) to kill harmful pathogens found in drinking water. In late June, I was thrilled to learn that I was one of 10 finalists in the 2012 Discovery Education 3M Young Scientist Challenge! and zinc oxide (ZnO)—to harness solar energy for water purification. When UV radiation strikes these photocatalysts, highly reactive species (super oxides and hydroxyl radicals) are formed. These species can oxidize harmful organics (such as those from pesticides or improperly discarded chemical waste) into water and carbon dioxide. The photocatalysts also help create pyrimidine dimers, which prevent pathogens’ DNA from replicating. In this way, TiO2 and ZnO remove organics and bacteria. In my entry video, I showed that the synergistic effect of TiO2 and ZnO was greater than using the two photocatalysts individually. For my prototype, I wanted to combine these two photocatalysts into an easy-to-use and cost-effective product. I tried several different adhesives and epoxies before concluding that cement would be the best binding agent to use in my composite. My first composite using cement, TiO2, and ZnO was effective but too heavy for practical use. I looked through 3M’s enormous index of products (all finalists had to incorporate a 3M product in their final prototype) and came across 3M Glass Bubbles: UV-transparent, lightweight, very strong microspheres. Adding these to my composite would reduce the amount of cement I needed, thereby reducing the weight as well. I created a novel photocatalytic composite of TiO2, ZnO, Cleaner Water by Deepika Kurup I A Summer of Experimentation Each finalist was assigned a mentor from 3M who would guide us through the innovation process over the summer. My mentor, Dr. James M. Jonza, is an inventor on over 45 patents and has received numerous awards from 3M. I spoke with Dr. Jonza over the phone for half an hour every week to discuss various scientific ideas, my experimental plan, and my test results. We also discussed how I would develop a water purification prototype based on the idea I had presented in my entry video. I planned to use two photocatalysts—titanium dioxide (TiO2) imagine 21 thinkstoCk

Table of Contents for the Digital Edition of Imagine Magazine - Johns Hopkins - January/February 2013

Imagine Magazine - Johns Hopkins - January/February 2013
Big Picture
In My Own Words
The Week I Turned Green
No Turning Back
Landsat: A Continuing Legacy of Earth Observation
Sensing Danger
The Black Gold Miners
Cleaner Water, Brought to You by Sunlight and Science
Journey to the Frozen Continent
CTY Paleobiology
Selected Opportunities & Resources
Innovation in the Real World
Off the Shelf
Word Wise
Exploring Career Options
One Step Ahead
Planning Ahead for College
Students Review
Creative Minds Imagine
Mark Your Calendar
Knossos Games

Imagine Magazine - Johns Hopkins - January/February 2013