Porous organic semiconductor/PET composite fiber for synergistically removal of hexavalent chromium and organic pollutants by sunlight driven

Abstract

: In this study, the porous graphite phase carbon nitride photocatalyst (P-g-C3N4) is prepared by CaCO3 template method, and then produce P-g-C3N4/T-Polyethylene terephthalate (T-PET) catalytic fiber by padding method. P-g-C3N4 can provide more actives sites than g-C3N4 is proved by Brunauer-Emmett-Teller (BET) and UV-visible diffuse reflectance test. P-g-C3N4 powder catalyst successfully supports on PET fiber and proves by scanning electron microscope, fourier infrared spectroscopy and X-ray diffraction spectroscopy. The photocatalytic performance of P-g-C3N4/T-PET catalytic fiber is tested by constructing single hexavalent chromium or hexavalent chromium/organic pollutant binary pollution system. The potential application value of P-g-C3N4/T-PET catalytic fiber is further explored by simulating the complex actual water environment. After 5 recycles, P-g-C3N4/T-PET catalytic fiber also has good catalytic performance. The mechanism of P-g-C3N4/PET photocatalytic degradation of organic pollutants is proposed through the capture agent experiment and electron paramagnetic resonance spectroscopy. Among them, •O2 - is the most important active species of P-g-C3N4 catalytic fiber, which is used for the oxidation of organic pollutants. At the same time, photoelectrons generated by the catalytic fiber are used to reduce hexavalent chromium. The efficiency of P-g-C3N4 to remove pollutants is improved by using PET fiber as a carrier, which not only solves the problem of difficult recovery of powder catalysts, but also provides more active sites.