Femtosecond pulsed laser-induced covalent bonding of SWCNTs: Toward high-performance flexible bending sensors

Single-Walled Carbon Nanotubes (SWCNTs), with their superior nanoscale properties, are supposed to be the ideal material for next-generation wiring. However, establishing chemical bonding between SWCNTs presents a formidable challenge. The interconnection process should be executed with precision, applying a heat source that induces a chemical reaction between SWCNTs without causing damage or introducing impurities. In this study, a high-energy laser beam was introduced to activate SWCNTs, causing them to chemical bonding with each other under the action of femtosecond pulse laser energy. Based on this technique, the electrical performance of the connected SWCNTs sensor was improved by nearly 63 %. After 1000 repeated bending cycles, the response value of the sensor decreases only slightly, confirming its long-term reliability and durability. The uniqueness of femtosecond pulse lasers was utilized to overcome the limitations of traditional thermal and mechanical processes to achieve selectively effective interconnection of SWCNTs, providing a new possibility for the connection of SWCNTs in future integrated applications.