Synergistic eminently active catalytic and recyclable Ag, Cu and Ag-Cu alloy nanoparticles supported on TiO2 for sustainable and cleaner environmental applications: A phytogenic mediated synthesis

Ag-Cu monometallic and bimetallic nanoparticles were prepared directly using aqueous extract of Walsura trifoliata supported on TiO2. The extract helps in the in situ immobilization of Ag, Cu and Ag-Cu alloy nanoparticles with face-centered cubic structure using phytochemical compounds as template and reducing agent at ambient conditions. The aqueous extract of W. trifoliata flower acts as reducing, binding, dispersion agent and plays a major role in the synthesis of the nanocomposites which was confirmed using GC-MS. The nanocomposite were characterized using UV–Vis, FTIR, XRD, TEM, SAED, EDS, and Raman Spectra techniques. The efficiency of prepared nanocomposite on the catalytic activity for the reduction and degradation of 4-Nitrophenol (4-NP), Methyl orange (MO), and Rhodamine B (Rh B) with sodium borohydride (NaBH4) were investigated in detail. The Ag-Cu/TiO2 bimetal nanocomposite exhibit very high activity for the degradation of dyes, confirmed using UV–Vis and HPLC analysis. In addition, Ag/TiO2, Cu/TiO2 and Ag-Cu/TiO2 nanocomposites exhibit good reusability with 100% conversion efficiency of 4-NP, MO and Rh B up to 6 successive cycles. The phytogenic mediated synthesis of metal nanocatalyst supported on TiO2 makes it an ideal platform for heterogeneous catalytic process and for potential application in a wide range of fields.