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A direct Z-scheme BiOBr/Bi 2 Sn 2 O 7 photocatalyst with abundant of surface OVs (Vo-BiOBr/Bi 2 Sn 2 O 7) has been designed and synthesized which is applied for photocatalytic degradation under visible light irradiation. The as-prepared Vo-BiOBr/Bi 2 Sn 2 O 7 heterojunctions with abundant surface OVs displays outstanding degradation performance and excellent stability. [Display omitted] Promoting charge migration and enhancing redox ability of photogenerated carriers are important for the development of highly efficient semiconductor-based photocatalyst. Here, BiOBr/Bi 2 Sn 2 O 7 heterojunction with oxygen vacancies (OVs) was constructed by homogeneously depositing Bi 2 Sn 2 O 7 nanoparticles on the Vo-BiOBr surface. The experimental results manifested that Vo-BiOBr/Bi 2 Sn 2 O 7 displayed better performance for rhodamine B, ciprofloxacin, and tetracycline degradation than counterparts without OVs. The characterization results proved OVs played the essential role for enhanced performance via improving the separation efficiency of charge carriers, increasing the visible light harvest, and lowering conduction band position. Moreover, mechanism study revealed that an inner electric field was built at the interface, leading to a Z-scheme path of photogenerated electron. This study provided an efficient strategy for designing highly efficient photocatalyst for solving environmental pollution. [ABSTRACT FROM AUTHOR]

An interfacial C-S bond bridged ZnS/C 3 N 5 S-scheme heterojunction was constructed for photocatalytic H 2 evolution. Benefiting from the interfacial covalent bond, enhanced internal-electric-field strength, and accelerated surface photocatalytic reaction, the photocatalytic H 2 production of ZnS/C 3 N 5 was 3.2 and 2.5 times higher than those of ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S bond. [Display omitted] • C-S bond is susceptive to preparation temperatures, and it is broken above 300 °C. • C-S bond promotes e − separation and improves H 2 O adsorption and activation behaviors. • IEF strength of ZnS/C 3 N 5 with opposite direction is 2.6 times than that of ZnS/C 3 N 4. • e − transfer respectively follow S-scheme and type-II pathway in ZnS/C 3 N 5 and ZnS/C 3 N 4. • H 2 yield of ZnS/C 3 N 5 is 3.2 and 2.5 times than ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S. An interfacial C-S bond bridged ZnS/C 3 N 5 heterojunction was constructed for photocatalytic H 2 evolution. Different from traditional type-II ZnS/C 3 N 4 heterojunction, the electron transfer followed S-scheme pathway, due to opposite internal-electric-field (IEF) directions in these two heterojunctions. The C-S bond formation was carefully investigated, and they were susceptive to the preparation temperatures. In photocatalytic reaction, C-S bond was functioned as the "high-speed channel" for electron separation and transfer, and the IEF strength in ZnS/C 3 N 5 was 1.86 × 108 V/m, 2.6 times higher than that in ZnS/C 3 N 4. Moreover, the C-S bond also altered the surface molecular structure of ZnS/C 3 N 5 , and hence the surface reaction was accelerated via improving H 2 O adsorption and activation behaviors. Benefiting from the S-scheme pathway, enhanced IEF strength, and accelerated surface reaction, the photocatalytic H 2 production over ZnS/C 3 N 5 reached up to 20.18 mmol/g/h, 3.2 and 2.5 times higher than those of ZnS/C 3 N 4 and ZnS/C 3 N 5 -300 without C-S bond. [ABSTRACT FROM AUTHOR]

"Double-yolk egg-like" Fe 3 O 4 /PBA@PPy nanoreactor is synthesized, where the confinement effect from the cavity, the protective effect from the PPy shell, and the magnetic property were successful integrated together. Therefore, it displayed the high degradation efficiency, low leaching, and rapid separation in Fenton-like reaction. [Display omitted] • k of Fe 3 O 4 /PBA@PPy-10 was 0.38 L·min·mol−1, 5.1 times than that of reference Fe 3 O 4 /PBA-10 in Fenton-like reaction. • The concentration of leached cobalt ions was reduced from 1.47 mg/L to 0.174 mg/L by the protective function from the PPy shell. • 84.5% of the degradation efficiency of the 1st cycle was still maintained after 4 cycles. • The core of Fe 3 O 4 make sure the catalyst can be rapidly separated by a magnet. • Mechanism of Fenton-like reaction is revealed in detail. Peroxymonosulfate (PMS)-based Fenton-like reaction is an effective technique for the pollutant degradation, and the Co-based metal organic frameworks displayed the excellent activity for the PMS activation. Nevertheless, how to further improve the catalytic activity, suppress the leaching of toxic cobalt ions, and realize the rapid separation were still challenges for practical application. In this work, a novel solution was proposed: encapsulating Fe 3 O 4 and Prussian blue analogue (PBA) into the polypyrrole (PPy) shell and constructing a "double-yolk egg-like" Fe 3 O 4 /PBA@PPy as a nanoreactor. In Fe 3 O 4 /PBA@PPy-10, the catalytic performance was remarkably enhanced with the help of confinement effect, and the degradation rate (0.38 L·min·mol−1) was 5.1 times than that of reference Fe 3 O 4 /PBA-10 (0.074 L·min·mol−1). In addition, the concentration of leached cobalt ions was reduced to only 0.174 mg/L by the protective function from the PPy shell. Moreover, the nanoreactor could be magnetically separated from the reaction solution due to the encapsulation of Fe 3 O 4 nanospheres, and 84.5% of activity still preserved after the 4th cycle. The main active species involved in Fe 3 O 4 /PBA@PPy-10 system was 1O 2 , while that in reference Fe 3 O 4 /PBA-10 system was OH. Electron spin resonance analysis and radical trapping experiment revealed that the different catalytic mechanisms were attributed to the confinement effect inside the hollow cavity. This work not only presents a feasible way to prepare rarely-reported double-yolk egg-like nanoreactor, but also provides a new insight to solve the bottlenecks in Fenton-like reaction. [ABSTRACT FROM AUTHOR]