Constructing S‐scheme heterojunctions with tunable interfacial oxygen vacancy via UiO‐66‐NH₂‐derived ZrO2‐x for efficient photocatalytic performance

Defects engineering is significant for photocatalytic environment remediation. To this end, visible‐light‐driven α‐Fe 2 O 3 /ZrO 2‐x S‐scheme heterojunction photocatalysts with optimal oxygen vacancy (O v ) defects are successfully synthesized via a two‐step method. Compared with pristine UiO‐66‐NH 2 ‐derived ZrO 2‐x and α‐Fe 2 O 3 , the heterojunction photocatalysts exhibit a wider range of visible light response and higher efficiency in separating photogenerated electron–hole pairs. Among them, the 5% α‐Fe 2 O 3 /ZrO 2‐x sample shows the best photocatalytic performance to the degradation of tetracycline (TC) (89.3%), in which the pseudo‐first‐order kinetic rate constants are 8.20 and 16.75 times that of pristine ZrO 2‐x and α‐Fe 2 O 3 , respectively. The outstanding photocatalytic degradation efficiency can be attributed to both the narrow‐bandgap ZrO 2‐x with visible light response and the formation of α‐Fe 2 O 3 /ZrO 2‐x S‐scheme heterojunctions. During the formation of heterojunctions, the concentration of oxygen vacancies (O v ) at the interface of α‐Fe 2 O 3 /ZrO 2‐x decreases monotonically with the increasing loading of α‐Fe 2 O 3 , thereby altering the electronic structure of the photocatalyst and forming the heterojunction firmly. In addition, the high stability implies the potential applications in fields of environment.