Preparation of tungstophosphoric acid/cerium-doped NH2-UiO-66 Z-scheme photocatalyst: a new candidate for green photo-oxidation of dibenzothiophene and quinoline using molecular oxygen as the oxidant
Résumé
The goal of this study was to introduce an effective visible-light induced photocatalytic system with a good ability for photocatalytic oxidative desulfurization (PODS) and denitrogenation (PODN) using molecular oxygen (O2) as an oxidant. In this regard, tungestophosphoric acid (PW12) was supported onto cerium-doped NH2-UiO-66 (PW12/Ce-NUiO-66) and employed for the photo-oxidation of dibenzothiophene (DBT) and quinoline (Qu). Herein, using cerium (Ce) as a “mediator” facilitated the separation of charge carriers, while NH2-UiO-66 remarkably enhanced the surface area with plentiful adsorption sites and shifted the adsorption edge of PW12to the visible region. The sum of these factors resulted in superior photocatalytic ability and maximum efficiency of 99 ± 1% was achieved by using 30PW12/Ce-NUiO-66 as the optimum photocatalyst in the PODN system and 89 ± 1% in the PODS system under visible light irradiation for 90 min. The traditional Z-scheme mechanism was proposed as the main pathway for this photocatalytic system.
Mots clés
Carrier mobility
Cerium
Light
Oxidants
Photocatalytic activity
Adsorption edges
Dibenzothiophenes
Maximum Efficiency
Oxidative desulfurization
Photocatalytic systems
Tungstophosphoric acid
Visible light induced
Visible-light irradiation
Molecular oxygen
cerium
dibenzothiophene derivative
oxidizing agent
oxygen
phosphotungstic acid
quinoline
uranium
adsorption
Article
catalyst
desorption
desulfurization
green chemistry
irradiation
photocatalysis
photooxidation
pore size distribution
pore volume
surface area