Method to create a hydrophilic environment within hydrophobic nanostructures

Copper and Nickel Nanoparticles Prepared by Thermal Treatment of Their Respective Cations Confined in Nanopores through High-Pressure Synthesis

“…MCM-41 metal preparation-Our pressure method, represented in Figure 1, was already used for the confinement of Cu II species in hydrophobic MCM-41 materials of varying pore size [20]. Here we extended this high-pressure synthesis to include Ni II cations to demonstrate that metal cation confinement is not exclusive to Cu II.…”

“…This solution was forced into the pores under a pressure of 4000 bar at room temperature. The pressure setup is shown in Figure 1 and was identical to the setup used in our previous work [20]. The pH of the solution was chosen for each cation to ensure that no precipitation of the respective hydroxide would occur during the pressure treatment.…”

“…The form and position of peaks in the 2900 and 800 cm −1 regions corresponding to the υ(C-H) stretching and δ(-CH 3 ) bending modes, respectively, remained intact for both MCM-Si-M materials. However, additional peaks at 1620 cm −1 and in the region of 3400 cm −1 appeared, indicating that adsorbed water [20] was present. Although the drying step was identical in both cases, the intensity of these two peaks was more important for the MCM-Si-Ni II material, indicating that more adsorbed water was present.…”

“…As silanol groups within the pores contribute to the adsorption and hydrogen bonding of water molecules, replacing the silanol hydrogen by Me3Si groups would mean that the adsorbed water could be attributed to the presence of the Cu II cations. Recently, we developed a high-pressure method for confining Cu II cations exclusively inside Mobil Composition of Matter 41 (MCM-41) hydrophobic nanopores [20]. Using this method, we extended the process to include Ni II cations and developed a specific and simple way to prepare well-dispersed copper and nickel NPs by using thermal treatments, without the use of any reducing agents.…”