Noble Metal Nanoparticles and Their Application as Sensors for Water Quality Monitoring: A Review

Abstract

Noble metal nanoparticles, including gold, silver, platinum, and palladium, have garnered significant attention for their potential applications as sensors in water quality monitoring. Despite extensive research on the individual synthesis and properties of these nanoparticles, a comprehensive review focusing on their collective application in detecting water pollutants has been lacking. This review is crucial as it addresses a significant gap in the literature, highlighting the unique capabilities of noble metal nanoparticles in environmental monitoring. We systematically examine various synthesis methods for these nanoparticles, including chemical reduction, electrochemical techniques, and green synthesis, providing a detailed overview of each approach's advantages and limitations. It further explores the unique properties and characteristics of noble metal nanoparticles, such as their high surface area, tunable optical properties, and excellent conductivity, which make them particularly suitable for sensing applications. The detection mechanisms of these nanoparticles as sensors are analyzed, focusing on their ability to detect various water pollutants through techniques such as surface plasmon resonance (SPR), electrochemical sensing, and colorimetric detection. Our comprehensive examination reveals that noble metal nanoparticles exhibit remarkable sensitivity and selectivity towards a wide range of contaminants, including heavy metals, organic compounds, and pathogens, offering promising solutions for real-time and on-site water quality assessment. The major findings underscore the significant potential of these nanoparticles in enhancing the accuracy and efficiency of water quality monitoring systems. This review provides a valuable resource for researchers and policymakers, emphasizing the transformative potential of noble metal nanoparticles in ensuring safe and clean water resources.