2D Bi2MoO6 nanosheets immobilized on electrospun 1D LaFeO3 hollow nanofibers: An efficacious direct Z-scheme p-n type heterojunction photocatalyst for removal of organic contaminants under visible-light irradiation

Abstract

Antibiotics have been widely used in the past few decades, but they are difficult to be completely decomposed by organisms and nature. Semiconductor photocatalysis has been demonstrated to be one of the most promising and efficient ways to remove antibiotics from water. In this work, to address the aforementioned issues, two-dimensional (2D) n-type Bi2MoO6 nanosheets fixed on one-dimensional (1D) p-type LaFeO3 hollow nanofibers are designed and prepared by combining an electrospinning with a solvothermal method via semiconductor energy level matching engineering, thereby forming an effective direct Z-scheme p-n type 2D/1D heterojunction photocatalyst. The optimized Bi2MoO6/LaFeO3 heterojunction photocatalyst displays the best-performing photocatalytic degradation rate of 92.31% for tetracycline hydrochloride (TCH) degradation under visible-light irradiation within 30 min. The excellent photocatalytic activity can be attributed to the broadening of spectral response range by the formation of direct Z-scheme p-n type heterojunctions, the large specific surface area of 2D/1D hollow nanofiber heterojunctions, the 2D/1D contact interface for fast carrier transfer channels and the internal electric field formed by direct Z-scheme p-n type heterojunctions. Importantly, this heterojunction photocatalyst exhibits broad-spectrum applicability, as it can degrade several organic pollutants such as ciprofloxacin (CIP), carbamazepine (CBZ), cefuroxime sodium (CRO), ibuprofen (IBU), bisphenol A (BPA) and methylene blue (MB) with degradation rates of 88.96%, 18.04%, 71.51%, 78.03%, 88.82% and 86.72%, respectively, in 120 min under visible-light irradiation. The preparative processes for the photocatalyst are optimized, the formation mechanism is advanced, and corresponding technology is established.