Synergistic effect of upconversion and LSPR effect in GdF3:Yb3+, Er3+@g-C3N4@Ag ternary photocatalyst for enhancing tetracycline hydrochloride photodegradation

Graphitic carbon nitride (g-C 3 N 4 ) is restricted by its narrow light absorption range, which results in low photocatalytic efficiency. To address this problem, a plasmon- and upconversion-enhanced ternary photocatalyst (denoted as GdF 3 @g-C 3 N 4 @Ag) was subtly designed and synthesized in situ. The g-C 3 N 4 nanosheets were encapsulated on the GdF 3 by a simple vapor deposition method, which has not been reported in the literature. The GdF 3 @g-C 3 N 4 @Ag composite exhibits full-spectrum responsiveness and remarkably improved photocatalytic activity in the degradation of tetracycline hydrochloride compared with plain g-C 3 N 4 . The degradation rate constant of the best-performing photocatalyst GdF 3 @g-C 3 N 4 @5%Ag (2.618 × 10 −2 min −1 ) is higher than that of g-C 3 N 4 (1.723 × 10 −2 min −1 ) under irradiation at λ ≥ 400 nm. This study develops a full-spectrum responsive photocatalyst based on GdF 3 @g-C 3 N 4 @Ag, showing its great potential to fully utilize the solar spectrum, and provides important insights into the construction of full-spectrum responsive photocatalysts.