Synthesis of Al-MCM-41@Ag/TiO₂ Nanocomposite and Its Photocatalytic Activity for Degradation of Dibenzothiophene

Abstract

Mesoporous Al-MCM-41@Ag/TiO2 nanocomposites were synthesized successfully by combining the sol-gel method and hydrothermal treatment, using titanium isopropoxide (TTIP), AgNO3, and Vietnamese bentonite as precursors of Ti, Ag, and Si, respectively. The synthesized materials were well characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption isotherm measurements, energy dispersive X-ray spectroscopy (EDX), UV-visible diffuse reflectance spectroscopy (UV-Vis/DRS), and X-ray photoelectron spectroscopy (XPS). The photocatalytic activity was evaluated by the photodegradation of dibenzothiophene (DBT) under both UV and visible light irradiation. MCM-41@Ag/TiO2 catalyst exhibited high catalytic activity for the oxidative desulfurization (ODS) of DBT reaching almost 100% conversions at 50°C after 2 h under UV and visible light irradiations. The significant enhanced degradation of DBT over Al-MCM-41@Ag/TiO2 might be due to the synergy effects of high surface area of MCM-41, well-distributed TiO2 anatase, and reduced electron-hole recombination rates due to the dispersion of Ag nanoparticles.

High CO Adsorption Performance of CuCl-Modified Diatomites by Using the Novel Method “Atomic Implantation”

“…Currently, clay minerals such as halloysite, dolomite, bentonite, Ilmenite, and diatomite have attracted a lot of interest because of their potential application or environmental treatment [18][19][20][21][22]. Clay-based adsorbents for adsorption of gases such as CO, CO 2 , CH 4 , H 2 S, heavy metal ions, and organic pollutants were also investigated.…”

Enhanced photocatalytic degradation of direct blue 71 dye using TiO2-PAA-GO composite in aqueous solution

“…However, its photocatalytic activity is limited by its low sensitivity in the visiblelight region and the fast recombination of photogenerated holes (h + ) and electrons (e -) [8]. To improve the photocatalytic performance of TiO 2 , it is combined with carriers such as graphene oxide (GO), MCM-41, SBA-15, and carbon nanotubes (CNT) [15][16][17]. Graphene oxide (GO) is an exciting material owing to its unique electron properties, flexibility, high transparency, high surface charge, good electrical conductivity, surface density, and mobility.…”

Highly efficient photocatalytic oxidative desulfurization of dibenzothiophene with sunlight irradiation using green catalyst of Ag@AgBr/Al-SBA-15 derived from natural halloysite

“…Recently, mesoporous silica was synthesized with kanemite (NaHSi2O5.3H2O) [32], metakaoline [33], coal fly ash [34], and bentonite [35]. In our previous research [22,36], we synthesized mesoporous silica Al-MCM-41 from natural bentonite with a BET surface area of 633 m 2 /g, pore volume of 0.94 cm 3 /g, and pore size of 8.64 nm, respectively. Halloysite was recently used as a silica and aluminum source to synthesize a mesoporous SBA-15 material.…”