Interface catalytic regulation via electron rearrangement and hydroxyl radicals triggered by oxygen vacancies and heavy metal ions

Abstract

Although the enhanced intrinsic activities of some nano-metal oxides are obtained by manufacturing oxygen vacancies (OVs), the effect of multiple roles of OVs are ambiguous. Herein, an interface catalytic regulation...

Ultrasonic controllable synthesis of sulfur-functionalized metal–organic frameworks (S-MOFs) and their application in piezo-photocatalytic rapid reduction of hexavalent chromium (Cr)

“…The superoxide radical (·O 2 – ) had a weaker oxidation ability than the hole [88] , and its main role in the reaction was to transfer electrons [88] , [89] , making the electrons migrate to the catalyst surface and more easily reduce Cr(VI) [88] , [90] . The hydroxyl radical (·OH), as a relatively weak active species in both oxidation and reduction [91] , could cooperate with the superoxide radical to play a certain role in electron transfer [91] , [92] , but it was not the main active species.

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Modulating paired Ir–O–Ir via electronic perturbations of correlated Ir single atoms to overcome catalytic selectivity

“…In the high-resolution XPS spectra of O 1s, the characteristic peaks near 529.8 and 531.6 eV were assigned to Vo and lattice oxygen (O L ) for Ir SAs/Co 3 O 4 , and the peak at 532.6 eV was due to hydroxyl groups (–OH) or surface-adsorbed water ( O ads ). 43 Compared with Co 3 O 4 and IrO 2 /Co 3 O 4 , the binding energy of O L in Ir SAs/Co 3 O 4 shifted negatively to 0.4 eV, while the V O shifted to a high binding energy of 0.3 eV, which elucidated the strong interaction between Ir and O. In addition, the V O content was reduced in Co 3 O 4 and IrO 2 /Co 3 O 4 , which was consistent with the results revealed by the EPR tests.…”