Uniformly deposition of iron phosphide quantum dots on the microscopic spongy B-C3N4 and its efficient degradation of ciprofloxacin by photo-self-Fenton process

Abstract

In this research, iron phosphide quantum dots (FeP QDs) are synthesized and anchored on the microporous spongy BxCN uniformly through a novel hydrothermal-phosphorization processes. FeP@BxCN shows excellent photo-self-Fenton capability and applies to eliminate CIP from aqueous solution. Results indicate both photocatalysis and self-Fenton processes contribute to CIP degradation (photocatalysis: 69.1 %; self-Fenton: 28.2 %). The decoration of FeP QDs could effectively suppress the recombination of photogenerated carriers and improve the photocatalysis performance. They also accelerate the transformation of in situ H2O2 to •OH radicals thus enhance the efficiency of self-Fenton process. Furthermore, FeP QDs shows pretty low consumption during the self-Fenton process because of the regeneration mechanism between cationic iron species, H2O2 and anionic phosphorus. The existence of intermediate valence iron (Feɛ+) and anionic phosphorus (Pɛ-) ensured the regeneration of Fe(II) and the circulation between Fe(II), Feɛ+ and Fe(III). Optimal CIP degradation efficiency could be achieved under neutral condition and the corresponding CIP removal efficiency are 97.3 % when the initial concentration is 30 mg•L−1 and reaction within 120 min. Results propose a meaningful exploration for antibiotics degradation via photocatalytic-self-Fenton technology.