Mesoporous Ag2O/ZrO2 heterostructures as efficient photocatalyst for acceleration photocatalytic oxidative desulfurization of thiophene

Abstract

The production of fuels with a low sulfur content has been paid significant attention in the manufacturing of petroleum refining due to the progressively severe environmental legislations obliged by governments worldwide. In this paper, for the first time, two dimensional mesoporous Ag2O/ZrO2 heterostructures were synthesized by a facile approach for thiophene photocatalytic oxidative desulfurization under visible-light exposure at room temperature. The Ag2O/ZrO2 heterostructures significantly enhanced the photocatalytic desulfurization of thiophene obeyed the pseudo-first-order model compared to pristine ZrO2 NPs. In particular, 1.5%Ag2O/ZrO2 photocatalyst exhibited better photocatalytic performance and the correspondent rate constant of 0.0235 min−1, which was promoted 5.35 times than that of pristine ZrO2 NPs (0.0044 min−1). The desulfurization rate of thiophene over 1.5% Ag2O/ZrO2 heterostructure was enhanced 3.7 times larger than that of pristine ZrO2 NPs. The thiophene was photocatalytically oxidized to CO2 and SO3. The photocatalytic performance of Ag2O/ZrO2 could be enhanced because of its synergetic effects, the intense visible-light harvest, rapid mobility of the thiophene to the active sites, a lower light scattering effect, and a large •OH radical contents formed. Moreover, the Ag2O/ZrO2 heterostructures revealed excellent stability toward the photocatalytic oxidative desulfurization of thiophene. A possible charge separation mechanism over mesoporous Ag2O/ZrO2 heterostructures was proposed.