China energy storage net news: a haze problem in northern China, one kind is caused by the burning of fallen leaves, but now the situation can be improved, that is raised the fallen leaves into a device can be used to store energy.
Many streets in this area of China are planted with paulownia trees. Sometimes they are called sycamore trees.Despite the Chinese government's ban, locals are still burning their leaves, exacerbating the problem.In Beijing alone, about two million tons of fallen leaves and plant waste are burned every year.
Professor ma hongfang and his colleagues from qilu university of technology have now figured out how to turn the leaf of the plane tree into an organic capacitor.The deciduous leaf can store energy like a battery and avoid the air pollution problem.
Caroline from Pennsylvania state university, said: "indeed, in the process of manufacturing the organic capacitance will release a small amount of carbon dioxide, but is not as the same amount of material produce as much as I would like to burn or decay.Either way, it's good to use waste material."The researchers cleaned and dried the leaves first, then ground them into fine powders.Then the powder scattered in the water, at 220 ° C temperature will be a mixture of flour and water heating in 12 hours, to filter out dust and pollutants, the process will produce brown powder carbon microspheres.
Expand the stomata
Add the microspheres in potassium hydroxide solution and reheating, up to 800 ° C to corrosion of the surface, leaving black powder in the tiny pores.These pores make the microspheres have a high surface area so they can store more energy.
"It's not new to turn biomass into capacitors," says Fred cannon of Penn state university. "others have done something similar, using wood or coal instead of falling leaves."In tests, however, defoliated devices proved to be supercapacitors, which can store more energy than similar capacitors made from coal.
Despite such characteristics, the researchers believe that the nature of the leaves varies, so it is difficult to commercialize the project.
"Falling leaves are not consistent with their characteristics, so I estimate that the characteristics of supercapacitors made from fallen leaves can vary," the researchers said.