Paper-based material performs like a supercapacitor
04 December 2015
Researchers have developed a new paper-like material consisting of nanocellulose and a conductive polymer that has an outstanding ability to store energy.
Photo: Thor Balkhed
One sheet, 15 centimetres in diameter and a few tenths of a millimetre thick has a capacitance of one Farad, which is similar to that of a supercapacitor. The material can be recharged hundreds of times and each charge only takes a few seconds.
"Thin films that function as capacitors have existed for some time," says Professor Xavier Crispin of Linköping University's Laboratory of Organic Electronics and co-author of an article describing the work in the journal, Advanced Science. "What we have done is to produce the material in three dimensions - we can produce thick sheets."
The material, dubbed 'power paper', has a structural foundation of nanocellulose (cellulose fibres processed into fibres 20nm in diameter). With the cellulose fibres in a solution of water, an electrically charged polymer (PEDOT:PSS), also in a water solution, is added. The polymer then forms a thin coating around the fibres. The covered fibres are in tangles, where the liquid in the spaces between them functions as an electrolyte.
Power paper is similar to pulp, which has to be dehydrated when making paper. The challenge now is to develop a process for producing the material on an industrial-scale.
Researchers from KTH Royal Institute of Technology, Innventia, Technical University of Denmark and the University of Kentucky were also involved in this work.