Upconversion-Agent\nInduced Improvement of g‑C₃N₄ Photocatalyst\nunder Visible Light

Abstract

Herein, we report the use of upconversion\nagents to modify graphite carbon nitride (g-C₃N₄) by direct thermal condensation of a mixture of ErCl₃·6H₂O and the supramolecular precursor cyanuric acid-melamine.\nWe show the enhancement of g-C₃N₄ photoactivity\nafter Er³⁺ doping by monitoring the photodegradation of\nRhodamine B dye under visible light. The contribution of the upconversion\nagent is demonstrated by measurements using only a red laser. The\nEr³⁺ doping alters both the electronic and the chemical\nproperties of g-C₃N₄. The Er³⁺ doping\nreduces emission intensity and lifetime, indicating the formation\nof new, nonradiative deactivation pathways, probably involving charge-transfer\nprocesses.