Paper is quite versatile, as a group of OSU scientists, working to create paper-printed electronics, has already shown. But who would’ve thought a piece of paper can actually store energy like a powerful supercapacitor? Well as it seems, this enterprising team of Swedish researchers surely did. Crafted using organic materials, the aptly-called “power paper” is capable of conducting ions and electrons; an ability that could pave the way for more efficient and sustainable energy storage.
Developed by scientists at Linköping University’s Laboratory of Organic Electronics, this smart, somewhat plastic-like paper is made by combining nanocellulose fibers with a special conductive polymer. For the research, recently published in the Advanced Science journal, the team subjected cellulose to extremely high-pressure water, which in turn disintegrated the fibers into nanocellulose only around 20 nanometers in diameter. Following this, the fibers were covered with a thin layer of electrically-charged polymer, and then brought together to form round, paper-like sheets. Speaking about the breakthrough, the team said:
Thin films that function as capacitors have existed for some time. What we have done is to produce the material in three dimensions. We can produce thick sheets… The covered fibres are in tangles, where the liquid in the spaces between them functions as an electrolyte.
A sheet of power paper, measuring around 15 cm in diameter and only 0.5 mm in thickness, can store up to 1 farad, which is same as the capacity of today’s supercapacitors. What is more, it can be recharged several hundred times, with each of the charging cycles taking only a few seconds to complete. Additionally, the material boasts some impressive green credentials, and is actually made of renewable cellulose and eco-friendly polymer.
Completely waterproof and non-toxic, this smart paper holds four different world records, including highest measured electric current in organic conductor, highest charge and capacitance among organic electronics, highest transconductance in a transistor and highest capacity to simultaneously pass electrons and ions. Furthermore, it is incredibly flexible, as proved by the researchers who created a stunning origami swan using a piece of the special paper.
The research was conducted in collaboration with the University of Kentucky, Sweden-based Innventia, KTH Royal Institute of Technology and the Technical University of Denmark. The team is currently working to make the technology ready for mass production. It has already received funding to build a specialized paper machine that will be able to produce the material on a much larger scale.