α-NiS/g-C3N4 Nanocomposites for Photocatalytic Hydrogen Evolution and Degradation of Tetracycline Hydrochloride
Huixian Qi, Chenyu Wang, Luping Shen, Hongmei Wang, Yuan Lian, Huanxia Zhang, Hongxia Ma, Yongcai Zhang, Jin Z. Zhang
Abstract
α-NiS/g-C3N4 nanocomposites were synthesized and used for photocatalytic hydrogen (H2) evolution and tetracycline hydrochloride (TC) degradation. The fabricated nanocomposites were characterized by XRD, XPS, SEM, TEM, UV-vis DRS, TRPL, and PEC measurements. Photocatalytic studies show that the hydrogen generation rate of the 15%-α-NiS/g-C3N4 nanocomposite reaches 4025 μmol·g−1·h−1 and TC degradation rate 64.6% within 120 min, both of which are higher than that of g-C3N4. The enhanced performance of the nanocomposite is attributed to the formation of a heterojunction between α-NiS and g-C3N4 that enhances visible light absorption, promotes the separation and transfer of charges, and inhibits the recombination of carriers. The photocatalytic mechanism of the α-NiS/g-C3N4 heterojunction nanocomposite is discussed in terms of relevant energy levels and charge transfer processes.