Green synthesis of ternary carbon dots (CDs)/MIL-88B (Fe)/Bi2S3 nanocomposite via MOF templating as a reusable heterogeneous nanocatalyst and nano-photocatalyst

Abstract

An environmentally friendly heterogeneous ternary carbon dots (CDs)/MIL-88B (Fe)/Bi2S3 nanocomposite was synthesized by a multistep method. In this study, we have studied low-temperature calcination with relatively inexpensive reactants. The sufficient CD arrays were generated by loading the glucose molecules into the pores of an as-obtained metal-organic framework (MOF), i.e. MIL-88B (Fe)), by heating to 200 °C. Fabricated nanocomposite structures were characterized by FT-IR, XRD, EIS, SEM, TEM, BET, and TGA techniques, demonstrating the decoration of the Bi2S3 on the CDs/MIL-88B (Fe) nanocomposite surface. MOF templating has been chosen as a systemic method for limited size CD formation inside MIL-88B (Fe) pores. The CD arrays also revealed an excellent efficacy for catalytic and photocatalytic applications. According to the experimental results, CDs/MIL-88B (Fe)/Bi2S3 with the highest electron-accepting and transporting properties capacity displayed the most increased activity as catalyst and photocatalyst. The catalytic and photocatalytic performance of obtained structures was investigated by reducing 4-nitrophenol (4-Nip) to 4-aminophenol (4-Amp) and decomposition of cationic Methylene Blue (MB) and anionic Acid Blue 92 (AB92) dyes under visible light irradiation, respectively. The current work exhibited CDs/MIL-88B (Fe)/Bi2S3 nanocatalyst as a potent multifunctional composite to remove organic components in the presence of reducing agents and visible light, which can be employed for wastewater treatment applications.