Oxygen-doped graphite carbon nitride as a fiber coating material for headspace solid-phase microextraction of organic phosphate esters

Efficient enrichment of trace organic phosphate ester (OPEs) pollutants from complex matrixes is essential for chromatographic analysis. Herein, oxygen-doped graphite carbon nitride (denoted as O-g-C 3 N 4 ) was fabricated though thermal polycondensation of urea using H 2 O 2 as an oxygen source. The resulting O-g-C 3 N 4 material was loose and had homogeneous pores structure, with a specific surface area of 73.74 m 2 /g. The O-g-C 3 N 4 was served as fiber coating material to create solid phase microextraction (SPME) device, with silica sol as adhesive for OPEs determination. Owing to the well-developed porosity of O-g-C 3 N 4 , which provides effective mass transfer channels for OPEs, the whole SPME procedure could be accomplished within 25 min. The O-g-C 3 N 4 fiber coating offers excellent mechanical strength and high stability and being workable after 180 sampling. The developed approach revealed a good linearity for OPEs in ultrapure water at the concentrations of 0.01–100 µg/L with the LODs between 0.001 µg/L and 0.003 µg/L. In addition, relative recoveries of 85.24% ∼99.73% were achieved in tap water and river water. These findings suggested that the oxygen-doped g-C 3 N 4 material has potential for headspace SPME of trace OPEs in various matrixes.