Researchers at TU Wien in Vienna have created a QR code so small it can only be read with an electron microscope. The code measures roughly 1.98 square micrometers, with individual pixels about 49 ...

A close-up look at a 20 dollar bank note reveals hidden textures, fibers, and micro-details invisible to the naked eye.

Many technological applications, such as sensors and batteries, greatly rely on electrochemical reactions. Improving these technologies depends on understanding how electrochemical reactions work.