Abstract
The development of cost-effective and highly sensitive SO2 sensors is an urgent task since SO2 causes worldwide serious environmental security and human diseases. Herein, a first photoelectrochemical (PEC) sensing platform for SO2 was constructed based on Ba2+ doped amorphous TiO2 hollow spheres. They were successfully prepared by SiO2 template method before in situ Ba2+ ions exchanging and doping. Before assay, SO2 was oxidized by hydrogen peroxide and generated H2SO4, which was further neutralized by NaOH resulting in the generation of Na2SO4. When it reacted with Ba2+-doped TiO2 hollow spheres, the produced BaSO4 nanoparticles leaded to the photocurrent remarkably decreased due to the photo-induced electron pathways shut down. The fabricated PEC sensor was linear with the concentration of SO42− in the range from 1 to 4000 pmol L−1 with a detection limit of 0.4 pmol L−1. The other conventional species did not interfere in the detection of SO42− in aqueous system and the fabricated PEC sensor was successfully applied in monitoring of SO2 in industry waste gas. It demonstrated good performance including wide dynamic linear range, high selectivity, ultrasensitivity, excellent stability and low cost. This strategy paves a new way for other similar air pollutants.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
