Impact of ligand on layered sulfur nanosheets/g-C3N4 nanocomposite for photocatalytic degradation

Abstract

Sulfur nanosheets (S-NSs), as a novel photocatalyst, was designed to composite with graphite phase nitrogen carbide (g-C₃N₄) to form a kind of new S-NSs/g-C₃N₄ (CNS) photocatalyst. The modulating effect of bovine serum albumin (BSA) or poly (3,4-ethylenedioxythiao)-polystyrene sulfonic acid (PEDOT:PSS) ligands on the photocatalytic activity of CNS nanocomposite was studied. The ligands mainly affect the band gap and conduction band potential of the photocatalyst, leading to different photocatalytic activities. When BSA was used as a ligand, the combine of S-NSs and g-C₃N₄ (CNS-B) cannot improve the photocatalytic activity for the degradation of Rhodamine B (RhB). When PEDOT:PSS was used as a ligand, the composite catalysts of CNS-P significantly improved the photocatalytic activity. The degradation efficiency of composite material CNS-P for RhB and Doxycycline hydrochloride (DOX) can reach 97 % (90 min) and 78 % (90 min). Since the combine of S-NSs and g-C₃N₄, the photoelectric conversion ability was enhanced and the carrier mobility was accelerated. The composite catalyst enhanced the redox ability and suppressed the recombination of photo generated carriers through Z-type charge transfer. This study give a reference for designing a new photocatalysts of two dimensional materials and also provide a potential feasibility for antibiotic degradation application.