Synthesis and antibacterial investigations of bismuth-doped Ag/Ag2S/gC3N4 heterostructure composite

Abstract The design of sustainable and eco-friendly materials for use as antibacterial agents has been challenging for material scientists. Herein, the bismuth-doped Ag/Ag 2 S/gC 3 N 4 heterojunction composite was prepared using as-prepared bismuth (III) N -methyl- N -phenyl dithiocarbamate, graphitic carbon nitride and silver nanoparticles in the presence of oleic acid at 220 °C. The composite was characterized using various techniques. Antibacterial activities of the composite were investigated against Gram-positive/Gram-negative bacteria. The antibacterial performance was compared to that of silver nanoparticles, bismuth nanoparticles, gC 3 N 4 and silver/graphitic carbon nitride (Ag/gC 3 N 4 ). In contrast to the results obtained with pure gC 3 N 4 , Ag/gC 3 N 4 and bismuth-doped silver/silver sulphide/graphitic carbon nitride (Bi@Ag/Ag 2 S/ gC 3 N 4 ) heterojunction exhibited reduced MIC (Ag/gC 3 N 4— 0.78 to 3.12 mg/mL, and Ag/Ag 2 S/gC 3 N 4 —0.78 and 1.56 mg/mL) and MBC (Ag/gC 3 N 4 —1.56 and 6.25 mg/mL, (Bi@Ag/Ag 2 S/gC 3 N 4 —1.56 and 3.12 mg/mL) against the Gram-positive and Gram-negative bacterial isolates examined in this investigation. Graphical abstract