Leaf fall gets new life as electronics

Abstract

Northern China has a smoky problem caused by autumn leaves. Now there could be a fix: simply turn them into devices that store energy. Many roads in this part of China are lined with trees of the genus Paulownia, sometimes called phoenix trees. Despite the government's disapproval, locals often burn the fallen leaves, worsening the country's notorious air pollution. In Beijing alone, about 2 million tonnes of leaves and other plant waste are burned every year. Now, Hongfang Ma at the Qilu University of Technology in Jinan and her colleagues have figured out how to turn phoenix tree leaves into supercapacitors.