Search

• A triple structure of CdS/Au/GQDs as a photo-to-electron conversion medium for the real-time detection of Cu2+ ions. • The detection limit of 2.27 nM was obtained, which is 10,000 fold lower than that of WHO's Guidelines (∼30 μM). • The photocurrent reduction was negligible after 30 days of storage, suggesting the high stability of the photoelectrode. • The real-time monitoring of Cu2+ ions in real water samples showed satisfactory results. • The excellent results acquired confirmed the capability of the studied photoelectrode as a practical detector for Cu2+ ions. Nowadays, increasing the risk for copper leaching into the drinking water in homes, hotels and schools has become unresolved issues all around the countries such as Canada, the United States, and Malaysia. The leaching of copper in tap water is due to a combination of acidic water, damaged pipes, and corroded plumbing fixtures. To remedy this global problem, a triple interconnected structure of CdS/Au/GQDs was designed as a photo-to-electron conversion medium for a real time and selective visible-light-prompt photoelectrochemical (PEC) sensor for Cu2+ ions in real water samples. The synergistic interaction of the CdS/Au/GQDs enabled the smooth transportation of charge carriers to the charge collector and provided a channel to inhibit the charge recombination reaction. Thus, a detection limit of 2.27 nM was obtained, which is 10,000 fold lower than that of WHO's Guidelines for Drinking-water Quality (∼30 μM). The photocurrent reduction was negligible after 30 days of storage under ambient conditions, suggesting the high stability of photoelectrode. Moreover, the real-time monitoring of Cu2+ ions in real samples was performed with satisfactory results, confirming the capability of the investigated photoelectrode as the most practical detector for trace amounts of Cu2+ ions. [ABSTRACT FROM AUTHOR]