Facile one-pot synthesis of a manganese-cerium dual-doped hydroxyapatite nanocatalyst using extract for photocatalytic degradation of methylene blue dye and catalytic reduction of 4-nitrophenol

In this work, a novel dual-metal-doped hydroxyapatite (HAp) nanocomposite, Mn-Ce/HAp, was synthesized by using Phyllanthus emblica (Indian gooseberry) extract. Advanced characterization tools such as powder X-ray diffraction, ultraviolet diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, and scanning electron microscopy, along with energy dispersive X-ray spectroscopy, elemental mapping, transmission electron microscopy, thermogravimetric analysis and X-ray photoelectron spectroscopy, were used to thoroughly characterize the as-synthesized nanocomposite. The photocatalytic and catalytic efficiency of the prepared nanocomposite were investigated in the same study. Mn-Ce/HAp exhibited outstanding performance in methylene blue (MB) dye degradation, with up to 94.8% degradation after just 50 minutes of solar light irradiation. There is no involvement of additional additives in the photodegradation process. HR LC-MS analysis was conducted to determine the major fragments of the degraded dye. A plausible mechanism of photocatalytic degradation was proposed based on various experimental findings. Furthermore, at ambient temperature, the nanocomposite Mn-Ce/HAp demonstrated excellent catalytic activity in the reduction of p -nitrophenol using NaBH 4 . The as-prepared nanocatalyst remarkably reduced 4-nitrophenol to 4-aminophenol completely in just 10 s. After five successive reaction cycles, Mn-Ce/HAp still exhibited around 95% of its initial conversion efficiency and photocatalytic efficacy, indicating the high stability and recyclability of the nanocatalyst. Novel Mn-Ce/HAp nanocatalyst was fabricated using green extract of Phyllanthus emblica and utilized it for the photodegradation of methylene blue dye and reduction of 4-NP to 4-AP.