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

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 (O-2) 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 PW12 to the visible region. The sum of these factors resulted in superior photocatalytic ability and maximum efficiency of 99 +/- 1% was achieved by using 30PW(12)/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.

Automated summary

This study introduced an effective visible-light induced photocatalytic system for photocatalytic oxidative desulfurization and denitrogenation using molecular oxygen as an oxidant. The composite of tungestophosphoric acid supported onto cerium-doped NH2-UiO-66 showed superior photocatalytic ability under visible light irradiation.