A hiker gets disoriented while on a desert trek when she comes upon a drying puddle left by a recent rain.
Consumed by thirst, miles from home, the hiker must decide whether to drink and risk infection from whatever bacteria are in the puddle, or endure dehydration. But that hiker might one day be able to drink worry free, thanks to a new kind of water purifier that uses sunlight and water to produce hydrogen peroxide, a powerful and common antiseptic.
The experimental water purifier, developed in the lab of Xiaolin Zheng, associate professor of mechanical engineering, is a variant of the better-known process of using solar energy to split water into hydrogen, a clean-burning fuel, and oxygen, a life-sustaining element. But, as the team describes in the journal Advanced Energy Materials, instead of fully splitting oxygen and hydrogen, the new process reduces oxygen and oxidizes water to produce hydrogen peroxide, or H2O2.
Even just a small amount will purify the water, she says. Hydrogen peroxide disinfects water at a level of tens of parts per million. That’s about two tablespoons in 25 gallons of water. In tests using tap water, the Stanford system easily reached well over 400 parts per million of H2O2 in five hours.
8-6-2021 (August 6, 2021) is the Snakiest day of the year and it’s also this year’s CircuitPython Day! The day highlights all things CircuitPython and Python on Hardware. See you there!
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.
Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7pm ET! To join, head over to YouTube and check out the show’s live chat – we’ll post the link there.
