A highly selective self-powered sensor based on the upconversion nanoparticles/CdS nanospheres for chlorpyrifos...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Visible light is commonly used in photoelectrochemical (PEC) self-powered sensing, but its high energy presents limitations.
• Near-infrared (NIR) light, a significant part of the solar spectrum, offers potential for improved PEC sensing.
• Developing sensors that effectively absorb and utilize NIR light is crucial for advancing self-powered sensing technologies.

Purpose of the Study:

• To create an efficient photoelectrochemical (PEC) self-powered sensor capable of utilizing near-infrared (NIR) light.
• To enhance the selectivity of the sensor for specific analytes using molecularly imprinted polymers (MIPs).
• To investigate the feasibility of using up-conversion nanoparticles (UCNPs) to broaden the spectral response of PEC sensors.

Main Methods:

• Combined up-conversion nanoparticles (UCNPs) with cadmium sulfide (CdS) semiconductor to form UCNPs/CdS photoactive material.
• Fabricated a self-powered sensor utilizing the UCNPs/CdS composite for NIR light excitation.
• Incorporated molecularly imprinted polymer (MIP) onto the photoanode for enhanced analyte recognition and selectivity.

Main Results:

• The developed UCNPs/CdS sensor effectively responded to NIR light, enabling self-powered operation through water oxidation and dissolved oxygen reduction.
• The sensor exhibited a linear increase in open-circuit voltage with increasing chlorpyrifos concentration from 0.01 to 100 ng mL⁻¹.
• The sensor demonstrated good selectivity and reproducibility in detecting chlorpyrifos, confirming the effectiveness of the MIP integration.

Conclusions:

• The integration of UCNPs with CdS enables efficient NIR light absorption, broadening the spectral response for PEC applications.
• The developed MIP-functionalized UCNPs/CdS sensor provides a selective and reproducible method for self-powered photoelectrochemical detection.
• This study offers a valuable foundation for designing practical and efficient PEC sensors with NIR light response capabilities.