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

Abstract

A facile synthetic methodology for the deposition of different concentrations of Ag nanoparticles (AgNPs) on α-Ni(OH) 2 sheets (α-Ni 1 (OH) 2 -Ag 0.5 , α-Ni 1 (OH) 2 -Ag 1 , α-Ni 1 (OH) 2 -Ag 2 , and α-Ni 1 (OH) 2 -Ag 3 ) is reported using N- [3-(trimethoxysilyl)propyl]diethylenetriamine (TPDT) silane. The TPDT aminosilane facilitates the formation of α-Ni(OH) 2 sheets and reduces the Ag + precursor to AgNPs, leading to the deposition of AgNPs on α-Ni(OH) 2 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 1 (OH) 2 -Ag 0.5−3 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 1 (OH) 2 -Ag composite sheet materials. The optical sensing property of α-Ni 1 (OH) 2 -Ag 0.5−3 composite materials toward toxic Hg 2+ ions were investigated using a UV−vis absorption spectroscopy technique. The α-Ni 1 (OH) 2 -Ag 2 composite material showed selective sensing behavior.