Design of 1D/2D Bi₂S₃/NiAl-LDH Heterojunction with Enhanced Photothermal-Photocatalytic Degradation of Tetracycline

Rational design of a dual-functional photothermal-photocatalytic heterostructure has received considerable attention in recent years. Herein, we proposed a 1D/2D Bi₂S₃/NiAl-LDH heterostructure system through a two-step hydrothermal method and used it for tetracycline degradation. Structural and morphological characterization techniques such as XRD, XPS, SEM, and TEM corroborated the successful anchoring of LDH nanosheets on flower-like Bi₂S₃. Various Bi₂S₃/NiAl-LDH heterostructure samples were prepared with different Bi₂S₃ contents (5, 7, 10, and 15 wt %) and denoted as BSL-<i>x</i> (<i>x</i> = 1, 2, 3, 4). The optimum composite (BSL-2) achieved a remarkable degradation efficiency of 95.7% under full-spectrum light irradiation. The photocatalytic reactions proceeded based on a pseudo-first-order kinetics model. The rate constant value for BSL-2 was 0.0162 min^-1, 4.90 and 4.26 times more than Bi₂S₃ and LDH, respectively. This considerable improvement in degradation efficiency is because of the intrinsic photothermal nature of bismuth sulfide, which enhances the light-harvesting capability of the Bi₂S₃/LDH heterostructure. Furthermore, 1D/2D heterojunctions caused charge carriers to separate and migrate faster, enhancing photocatalytic performance. Our article could yield a precious perspective on highly efficient 1D/2D heterojunctions based on the photothermal effect for various photocatalytic applications.