Palladium nanoparticles embedded PPy shell coated CNTs towards a high performance hydrazine detection through optical fiber plasmonic sensor

A facile in-situ solvothermal method has been proposed for the synthesis of palladium nanoparticles (PdNPs) embedded in polypyrmle (PPy) shell coated over carbon nanotubes (CNTs). The synergistic modulation of physicochemical properties of PdNPs/PPy@CNTs nanocomposite so prepared upon interaction with hydrazine has been explored for the surface plasmon resonance (SPR) based sensing on optical fiber substrate with silver as plasmonic material. The efficacy of the nanocomposite has been probed for 0-1500 nM hydrazine concentration range. The effects of the composition of nanocomposite, thickness of the sensing layer and the pH of the hydrazine solution have been studied to obtain the best sensing performance. The sensor possesses highest sensitivity of 0.09 nm/nM for lowest concentration of hydrazine with limit of detection (LOD) of 20 nM. The specificity of the probe has been tested by using several other interfering analytes. The proposed probe has been found to be feasible for the detection of hydrazine in ground water with high stability, accuracy and reproducibility. The proposed optical fiber probe could be very promising for the hypergolic fuels like hydrazine due to the facility of online remote monitoring for an early detection of any leakage in such combustible environments.

Automated summary

A facile in-situ solvothermal method was used to synthesize PdNPs/PPy@CNTs nanocomposite, which showed high sensitivity and specificity for sensing hydrazine in groundwater. The nanocomposite's performance was optimized by adjusting composition, thickness, and pH, with a highest sensitivity of 0.09 nm/nM and a limit of detection of 20 nM, making it promising for early detection of hydrazine leakage in combustible environments.