When researchers are studying how to promote the future of flexible, wearable electronic devices and biosensors, a new technology to synthesize specific materials may be the answer.
Materials such as atomic thin tin sulfide (SnS) are predicted to exhibit inherent flexibility and strong piezoelectric properties, and convert mechanical force or motion into electrical energy. Piezoelectric devices can sense sudden changes in acceleration and be used to trigger airbags of automobiles, while more sensitive devices can identify changes in the direction of mobile phones or form the basis of sound and pressure sensors.
More sensitive piezoelectric materials can provide power for micro devices such as biosensors implanted in human body by using small voltage generated by extremely small mechanical displacement, vibration, bending or stretching, thus eliminating the need for external power supply.
These impressive characteristics make SnS and other materials possible candidates for flexible nano-generators, which can be used in wearable electronic devices or internal self-powered biosensors. However, this potential application is limited by the synthesis of large, highly crystalline single-layer tin sulfide, which is difficult due to the strong coupling between layers.
However, a new cooperative research published by RMIT University and the University of Sydney, New South Wales in Nature Newsletter seems to have solved this problem, using a new liquid metal technology developed by RMIT to synthesize materials.
High durability and flexibility
This unprecedented synthesis technology involves van der Waals peeling off the surface of tin when it melts in the surrounding hydrogen sulfide gas. The gas decomposes at the interface and sulfides the surface of the melt to form SnS.
This method based on liquid metal allows scientists to extract uniform and large-scale single-layer SnS with the smallest grain boundaries. In addition, the measurement proves that the material has abnormal peak generation voltage and load power, as well as high durability and flexibility.
According to this research, because the synthesized single-layer SnS can be commercially applied to nano-power generation equipment or sensors for collecting human mechanical actions, the research results are a step towards wearable devices based on piezoelectric, flexibility and energy collection.