Around 783 million, or nearly 1 in 10 people around the world lack access to clean drinking water, according to UNICEF. This number is huge and there are indeed various technologies out there to help provide safe drinking, however, this is not the case. These technologies require lots of energy and expensive infrastructure which has a negative impact on the poor. To eliminate this problem, researchers have recently been working on the usage of solar stills as a solution by making it cheap and more effective for those in need. This is a device that uses the sun to evaporate dirty water and condense the vapor into safe drinking water. Initially, these solar stills were expensive and large that could only produce water for a small family, however, researchers soon developed a new material on the solar steel that speeds the evaporation and provides clean drinking water for many families in need.
The making of the solar still was very complex and researchers faced several problems during the process. At the very beginning, researchers faced a problem in the output of the solar stills because of how slow it was, producing only about .3 liters of water per square meter of the covered water while the average person requires 3 liters of water a day. Operating with this device can only produce 1.6 L/h/m2. Guihua Yu, a materials scientist reported a way to provide a solution to this problem. This solution was with the involvement of hydrogels (a polymer mixture that forms a 3D porous.) Also, Yu and his colleagues created a gel-like sponge of 2 polymers. One is a water-binding polymer called polyvinyl alcohol (PVA) and the other was a light absorber called Plypyrrole (PPY). Inside of the gel was a layer of water molecules that were bonded tightly to the PVA, resulting in hydrogen bonds. Yu called this the “intermediate water molecules” which evaporated more willingly than regular water. Using this Technology, Yu solar still produced 3.2 L/h/m2 which is twice as much as the initial device.
Peng Wand, an environmental engineer also agrees and states that “This is a fantastic starting point”, after noticing what Yu and his colleagues accomplished. This device can have a huge impact on those who are unable to provide themselves with safe drinking water and is an amazing start to something big that can aid the lives of millions of people across the world.