The Novel Z-Scheme Ternary-Component Ag/AgI/α-MoO3 Catalyst with Excellent Visible-Light Photocatalytic Oxidative Desulfurization Performance for Model Fuel

Abstract

The novel ternary-component Ag/AgI/α-MoO3 (AAM) photocatalyst was successfully fabricated by a facile hydrothermal method combined with a charge-induced physical adsorption and photo-reduced deposition technique. X-ray diffraction, scanning/transmission electron microscope, X-ray photoelectron, UV-vis diffuse reflectance, photoluminescence and electrochemical impedance spectroscopy were employed to characterize the composition, morphology, light-harvesting properties and charge transfer character of the as-synthesized catalysts. The ternary-component AAM heterojunctions exhibited an excellent visible-light photocatalytic oxidative desulfurization activity, in which the AAM-35 (35 represents weight percent of AgI in AAM sample) possessed the highest photocatalytic activity of the conversion of 97.5% in 2 h. On the basis of band structure analysis, radical trapping experiments and electron spin resonance (ESR) spectra results, two different catalytic mechanisms were suggested to elucidate how the photogenerated electron-hole pairs can be effectively separated for the enhancement of photocatalytic performance for dual composites AM-35 and ternary composites AAM-35 during the photocatalytic oxidative desulfurization (PODS) of thiophene. This investigation demonstrates that Z-scheme Ag/AgI/α-MoO3 will be a promising candidate material for refractory sulfur aromatic pollutant’s removal in fossil fuel.

Altered Properties of TiO2 for Photocatalytic Oxidative Desulphurisation

“…Pure TiO2 has a significant absorption edge located at 380 nm, demonstrating that it is simply an ultraviolet-driven catalyst. The absorption edge of the composite is substantially extended with the incorporation of Cu species, indicating a probable interaction between Cu dopant and TiO2 support [19].…”

Recent Advances and Challenges in Developing Technological Methods Assisting Oxidative Desulfurization of Liquid Fuels: A Review

“…119 BiVO 4 is an n-type semiconductor with a bandgap of about 2.4 eV that is a powerful photocatalyst under visible light, 120 whereas cuprous oxide (Cu 2 O) is a p-type semiconductor with the bandgap of about 2−2.5 eV that is transparent for only part of the visible light range. 121 ZnO is an n-type semiconductor with a bandgap of 133 Ag-AgBr/ Al-MCM-41, 134 Ti−Al−SBA-15, 135 C/TiO 2 @MCM-41, 136 graphene oxide (GO), 137 Ag-BiVO 4 , 138 Pt-RuO 2 /BiVO 4 , 139 MoO 3 -TMU-5, 140 C/TiO 2 @MCM-41, 141 Ti 3 C 2 /g-C 3 N 4 , 142 CeF 3 /g-C 3 N 4 , 143 g-C 3 N 4 /ZnTcPc, 144 MTcPc/SnO 2 , 122 Ni− Co 2 layered double hydroxides (LDH)/Fe 3 O 4 , 145 Ni−Fe 2 LDH, 145 Co−Fe 2 LDH, 145 Fe 3 O 4 @SiO 2 /Bi 2 WO 6 /Bi 2 S 3 , 146 Cu/Cu 2 O/BiVO 4 /Bi 7 VO 13 , 120 AgCl/PbMoO 4 , 147 BiVO 4 (CoCuAl/BiVO 4 ), 148 BiP 1−x V x O 4 /ATP, 149 Ag 2 WO 4 / Mn 3 O 4 , 150 Ag/AgI/α-MoO 3 , 151 AgI/Bi 2 O 3 , 152 and Ag− Bi 2 WO 6 , 153 were employed in the PODS process.…”

“…143 More research is tabulated in Table 2. The light sources for photoirradiation include high-pressure Hg lamps of 100 W, 137 125 W, 134 and 250 W; 154 the Hg−xenon lamp of 200 W; 123 xenon lamps of 300 W, 126,127,139,140,142 350 W, 129 and 450 W; 134 tungsten lamps of 250 W 145 and two 300 W tungsten lamps (600 W); 136 metal halide lamp of 400 W; 138,151 xenon-arc lamp of 500 W; 153 UV light of 35 W; 135 and two UV germicidal and one iodine−tungsten 155 lamps. The mechanisms of the photocatalytic desulfurization of ZnTcPc/SnO 2 and BiP 1−x V x O 4 /ATP photocatalysts are shown in Figures 8 and 9.…”

Desulfurization through Photocatalytic Oxidation: A Critical Review

“…[27] These free radicals have adequate redox ability to oxidize the sulfurcontaining compounds into less harmful or non-hazardous substances. [28,29] Since then, the research progress on PODS has witnessed a significant improvement with various ranges of photocatalysts from metallic inorganic substances to metal-free organic polymers, such as CeO 2 , [30] Fe 2 O 3 , [31] MoO 3 , [32] Cu 2 O, [33] TiO 2 , [34] SnO 2 , [35] WO 3 [36] and g-C 3 N 4 . [37] However, there are still research obstacles to be addressed, including the insufficient Xiaoyu Zhou is now a master student in the College of Chemistry and Chemical Engineering at Yangzhou University (China), under the supervision of Prof. Chengyin Wang.…”