"Miniature, wearable and electronic gadgets are becoming more and more common in our daily life," said Sozan Darabi, a doctoral student in the Department of Chemistry and Chemical Engineering at Chalmers University of Technology. But at present, they tend to rely on materials that are rare or, in some cases, toxic. They also lead to the gradual accumulation of "mountains" of e-waste. At present, organic and renewable materials are really needed for electronic textiles.”
Darabi and his team have had some success in developing conductive fibers made of silk, but now they have turned their attention to cellulose that has great potential. The technique starts with lignocellulosic threads, which are stained with ink based on a conductive biocompatible polymer called PEDOT: PSS. This "roll-to-roll" coating process turns the thread into a conductive thread, so that the team claims that the cellulose thread they created has a record high conductivity, which can be further improved by adding silver nanowires.
The resulting thread can be sewn into fabric on a household sewing machine to produce thermoelectric textiles that generate electricity when heated on one side. The team provided an example of body temperature, claiming that the textile can generate about 0.2 microwatts of electricity at a temperature difference of 37℃ (assuming a person is standing in a cold environment).
Sozan Darab said: "This cellulose thread can be made into clothes with built-in electronic and intelligent functions and is made of non-toxic, renewable and natural materials."
This kind of clothes can work in a range of areas, but scientists think it has special potential for medical treatment because they can be used to monitor different health indicators. The use of cellulose should increase the recyclability of finished products, although at present these threads can only undergo five machine washes without the loss of conductivity.
"Cellulose is a magical material that can be extracted and recycled sustainably, and it will be used more and more in the future," said Christian Müller, leader of the study. "When the product is made of uniform materials or as few materials as possible, the recycling process will become easier and more effective. From another perspective, cellulose thread is very promising for the development of electronic textiles."
The study was published in ASC Applied Materials & Interfaces.
Source: cnBeta New Atlas