Amine-Functionalized Silane-Assisted Preparation of AgNP-Deposited α-Ni(OH)₂ Composite Materials and Their Application in Hg²⁺ Ion Sensing

A facile synthetic methodology for the deposition of different concentrations of Ag nanoparticles (AgNPs) on α-Ni(OH) sheets (α-Ni(OH)-Ag, α-Ni(OH)-Ag, α-Ni(OH)-Ag, and α-Ni(OH)-Ag) is reported using -[3-(trimethoxysilyl)propyl]diethylenetriamine (TPDT) silane. The TPDT aminosilane facilitates the formation of α-Ni(OH) sheets and reduces the Ag precursor to AgNPs, leading to the deposition of AgNPs on α-Ni(OH) sheets. UV-vis absorption spectroscopy, transmission microscopy analyses, X-ray photoelectron spectroscopy, X-ray diffraction, and attenuated total reflectance-Fourier transform infrared spectroscopy techniques were used to characterize the prepared α-Ni(OH)-Ag composite materials. High-angle annular dark-field scanning transmission electron microscopy-energy-dispersive X-ray spectroscopy mapping images and scanning electron microscopy-energy-dispersive X-ray spectroscopy mapping images were recorded to understand the α-Ni(OH)-Ag composite sheet materials. The optical sensing property of α-Ni(OH)-Ag composite materials toward toxic Hg ions were investigated using a UV-vis absorption spectroscopy technique. The α-Ni(OH)-Ag composite material showed selective sensing behavior.