Carbyne enriched nanostructures for gas sensing applications: Synthesis and characterization

Among the various forms of carbon nanomaterials, one-dimensional sp-hybridized carbon, known as Carbyne, has been elusive and challenging to synthesize due to its chemical instability. Consequently, the properties of Carbyne have not been fully explored. Recent advancements have allowed the successful synthesis of finite-length Carbyne chains in the laboratory through novel techniques such as ion-assisted pulse plasma deposition (IA-PPD) and laser ablation in liquids (LAL). These methods produced hybrid nanostructures of sp³ and sp² carbon enriched with Carbyne. In this work, we report the synthesis and characterization of these Carbyne nanostructures to gain a deeper understanding of their unique properties. Their potential as sensing materials in quartz crystal microbalance (QCM) sensors was examined for room-temperature pollutant detection. Characterization results revealed a higher concentration of Carbyne in the LAL samples compared to the IA-PPD samples, which corresponded to superior gas sensing performance. In tests with various analytes, LAL Carbyne exhibited greater selectivity for ammonia gas. The sensor demonstrated a moderate response time of 4.7 min with full recovery in approximately 9.3 min. However, compared to other available carbon materials, the sensitivity of Carbyne was found to be relatively low, highlighting the need for further research to optimize Carbyne synthesis and sensor fabrication.