A freestanding SiO2 ultrathin membrane with NiCu nanoparticles embedded on its double surfaces for catalyzing nitro-amination.

Herein, a new two-dimensional (2D) ultrathin-nanostructure of NiCu-SiO2 has been explored through synchronously assembling NiCu nanoparticles (∼6 nm) on the double surfaces of the freestanding SiO2 ultrathin membrane by the in situ reduction of the NiCuSiO3-hydroxide precursor under H2. These 2D ultrathin-nanostructures of NiCu-SiO2 have high surface area and extremely high stability of morphology and thus can well embed the in situ formed NiCu NPs to achieve excellent catalytic cycling stability. When the NiCu-SiO2 nanocomposite is used to catalyze the amination reaction of 4-nitrophenol, the reaction selectivity is as high as 99%, and no obvious performance decay appears after 20 cycles. Moreover, the designed nanocatalyst has wide applications in other nitro-amination reactions.