Transformation of Cu(OH)2 to mesostructural copper-silicate in alkaline silicate solution

Abstract

Mesoporous materials with high surface area, tunable pore size, and large pore volume have applications in catalysis, adsorption, and optical devices. While the templating method has been used widely to synthesize these materials, removing the organic template leads to energy and chemical waste, and the emission of CO2 greenhouse gas. Here, a new non-organic templating method, based on structural transformation, is proposed to prepare mesostructural copper silicate with a high surface area (425 m2g-1) and large pore volume. This mesostructural transformation is already achieved by hydrothermally treating the Cu(OH)2 crystalline precipitate in an alkaline silicate aqueous solution. The copper silicate platelets obtained from a 5-day hydrothermal treatment in silicate solution have mesopores of about 3.5 nm. For the applications in absorption and catalyst application, the copper silicate has a high absorption efficiency (∼67%) and a fast removal rate toward PH3 gas at 600 ppb and a high-performance catalyst (yield of phenol derivatives about 86%) for the C–O coupling reaction. The mesostructural copper silicate platelets offer a cost-effective and environmentally friendly production method due to their flexible and straightforward preparation process. The synthetic route provides a promising approach to preparing different mesoporous metal silicates.