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The construction of a Z-scheme heterojunction favors the improvement of the photocatalytic activity of photocatalysts. Herein, the LaVO 4 /Bi 3 O 4 Cl Z-scheme heterojunction was designed reasonably by the method of in situ growth. The obtained heterojunction was further used as a photocatalyst for the degradation of ofloxacin (OFX), an antibiotic, in wastewater. The degradation efficiency of OFX by the optimal sample (LBC-2) was 94.3 % and the values of k were about 114.7 and 2.4 times those of LaVO 4 and Bi 3 O 4 Cl, respectively. In addition, LBC-2 maintained high activity after 4 cycles. The significantly reduced recombination rate of carriers in LBC-2 was reflected by the results of the photoluminescence (PL), photocurrent (PC), and electrochemical impedance spectroscopy (EIS) studies. The degradation pathways of OFX were proposed accounting to the intermediates detected by liquid chromatography-mass spectroscopy (LC-MS). Toxicity estimations showed that the toxicity of some intermediates decreased. This work provides new insight into the development of Z-scheme photocatalysts for the removal of antibiotics as pollutants. • Novel Z-scheme LaVO 4 /Bi 3 O 4 Cl composite photocatalysts were synthesized. • LaVO 4 /Bi 3 O 4 Cl composites exhibited excellent activity for ofloxacin degradation. • The apparent rate constant for ofloxacin degradation was about 114.7 and 2.4 times as that of LaVO 4 and Bi 3 O 4 Cl. • Z-scheme heterojunction boosted the fast transfer of charge carriers. • The degradation pathway of ofloxacin was deduced. [ABSTRACT FROM AUTHOR]

Direct Z-scheme Bi 3 TaO 7 –CdS semiconductor materials were synthesized via hydrothermal method. The activity of the composites was investigated by the ciprofloxacin (CIP) degradation under visible light irradiation. Bi 3 TaO 7 –CdS composite catalysts all exhibited enhanced photocatalytic performances compared to both single photocatalysts (Bi 3 TaO 7 and CdS). The characteristics of the morphology and structure, the photoelectric properties and the composition of chemical elements of these samples have been studied extensively. Besides, capture experiments demonstrated that superoxide radical and hole worked together for the CIP degradation. The optimal catalyst exhibited stable CIP degradation activity in four cycles repeating experiments. Finally, a possible Z-scheme charge migration mechanism was proposed for the Bi 3 TaO 7 –CdS composite photocatalysts. Three possible pathways were proposed for the CIP degradation based on the detected intermediates by LC/MS. This work provided a feasible idea for the further research of Z-scheme photocatalysts for the emerging contaminants degradation. • CdS/bismuth tantalate composite photocatalysts were synthesized for the first time. • The charge transfer followed Z-scheme mechanism. • The photocatalyst exhibited enhanced performance for CIP degradation of ciprofloxacin compared to Bi 3 TaO 7 and CdS. • The mechanism for the enhanced activity was discussed deeply. • The degradation pathways were deduced based on the detected intermediates. [ABSTRACT FROM AUTHOR]

Quasi two-dimensional perovskite solar cells (Q-2D PSCs) has attracted the attention of many researchers in recent years due to improved stability compared to their three-dimensional (3D) counterparts. However, the insulation of organic cation could hinder charge transfer between the octahedral sheets, thereby decreasing photoelectric performance of Q-2D PSCs. Here, the study of the synergistic effect of MACl and GuSCN on crystal orientation and quality of films based on the 4F‐PEA 2 MA 4 Pb 5 I 16 perovskite are reported. The Q-2D perovskite film exhibits more vertical orientation growth and lower trap-state density with the effect of dual additive. As a result, the device obtained a power conversion efficiency (PCE) of 15.05% for planar p-i-n solar cell using the Q-2D perovskite film with dual additive, which retained an average of 85% of their initial PCEs after 300 h in an ambient environment with humidity of 50 ± 10%. This result indicates that the use of dual additive MACl and GuSCN is an effective way to adjust the crystal orientation and quality of perovskite films, which are key factors to influence the performance of Q-2D PSCs. • The Q-2D perovskite film 4F‐PEA 2 MA 4 Pb 5 I 16 with dual additives (MACl and GaSCN) was prepared for the first time. • With the synergistic effect, the high-quality Q-2D perovskite film with more vertical orientation was obtained. • There was a larger concentration window of GaSCN additive in the presence of MACl due to their synergistic effect. • Compared with the Q-2D PSCs without additive, the PCE of Q-2D PSCs based on dual additives increased by 1.76 times. [ABSTRACT FROM AUTHOR]