Synchronized wet-chemical development of 2-dimensional MoS2 and g-C3N4/MoS2 QDs nanocomposite as efficient photocatalysts for detoxification of aqueous dye solutions

Abstract

The photocatalytic performance of graphitic carbon nitride (g-C3N4) is improved by the introduction of molybdenum disulfide (MoS2) quantum dots (QDs), aiming the enhanced visible light absorbance in resultant 2-dimensional g-C3N4/MoS2, termed as GCN/MoS2 hereafter. A novel synthetic approach i.e., pseudo-successive ionic layer adsorption and reaction (p-SILAR) was employed to deposit MoS2 QDs on g-C3N4 and to salvage 2-dimensional MoS2 concomitantly. The results of the photocatalytic activity affirm that GCN/MoS2 worked as a better photocatalyst than the pure g-C3N4, while salvaged MoS2 also showed reasonable degradation of Rhodamine-B (RhB) dye. The average pore size (measured with BET analysis) of GCN/MoS2 was reduced to 31.91 nm from 33.11 nm (for g-C3N4), indicating effectual nanoscale deposition of MoS2 which resulted in a decrease in the overall bandgap alignment of the composite from 2.8 eV to 2.2 eV. In-depth material characterization and photocatalytic analysis was carried out to affirm that p-SILAR serves as a suitable synthesis route for the development of GCN/MoS2 nanocomposite as well as salvaged MoS2.