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Photocatalysis is the most promising green approach to solve antibiotic pollution in water, but the actual treatment effect is limited by photocatalytic activity. Herein, Bi and BiOCl were loaded onto the surface of Ce-MOF (metal–organic framework) using an electrostatic adsorption method, and a special ternary heterojunction of Ce/Bi/BiOCl was successfully prepared as a photocatalyst for the degradation of tetracycline (TC). FTIR demonstrated that the obtained photocatalyst contains functional groups such as -COOH belonging to Ce-MOF and characteristic crystal planes of Bi and BiOCl, indicating the successful construction of a ternary photocatalyst. The results of UV–vis absorption spectra confirm that the band gap of Ce/Bi/BiOCl heterojunction is reduced from 3.35 eV to 2.7 eV, resulting in an enhanced light absorption capability in the visible light region. The special ternary heterojunction constructed by Ce-MOF, Bi, and BiOCl could achieve a narrow band gap and reasonable band structure, thereby enhancing the separation of photogenerated charges. Consequently, the photocatalytic performance of the Ce/Bi/BiOCl ternary heterojunction was significantly enhanced compared to Ce-MOF, Bi, and BiOCl. Therefore, Ce/Bi/BiOCl can achieve a photocatalytic degradation rate of 97.7% within 20 min, which is much better than Bi (14.8%) and BiOCl (67.9%). This work successfully constructed MOF-based ternary photocatalysts and revealed the relationship between ternary heterojunctions and photocatalytic activity. This provides inspiration for constructing other heterogeneous catalysts for use in the field of photocatalysis. [ABSTRACT FROM AUTHOR]

This work reports the effective preparation of a bimetallic metal–organic framework CoNi-MOF@MoS2 core–shell Z-scheme heterojunction photocatalyst via a two-step hydrothermal method. MoS2 nanoflowers uniformly grow on the multilayer CoNi-MOF exterior. MoS2 can be added to the system to improve its specific surface area and provide enough surface active sites for photocatalysis. The resultant CoNi-MOF@MoS2 has a broad-spectrum response, which is favorable for promoting the photocatalytic process. Under visible light irradiation, CoNi-MOF@MoS2 has a high hydrogen evolution efficiency of 478.6 μmol h−1 g−1. It also activates peroxymonosulfate, and the photocatalytic degradation rate of RhB pollutants in water can be up to 99.3% within 40 min, which is several times higher than that of the CoNi-MOF. The presence of the distinctive core–shell Z-scheme heterojunction structure is responsible for efficient charge separation and the enhanced photocatalytic performance. The high stability of CoNi-MOF@MoS2 also implies its potential applications in fields of environment and energy in future. [ABSTRACT FROM AUTHOR]

Porous organic polymers have an outstanding performance in the field of photocatalysis with the advantage of diverse structure composition and purposeful molecular design. However, the inherent high impedance and poor electrical conductivity of organic semiconductors still restrict the charge transfer efficiency and thus discount the photocatalytic performance. Herein, the study reports a highly conductive covalent triazine framework (CTF) loading carbon quantum dots (CQDs) into porous as electron transport medium. The addition of CQDs (0.5 wt%) can enhance the electronic conductivity of CTF by tenfold. In addition, the as‐prepared CQD‐CTFs express much‐promoted charge separation and transfer efficiency. Furthermore, the embedded CQDs can improve the oxidization capacity and increase the affinity of H+ due to the more negative zeta potential. The enhanced oxidizing ability and increased H+ affinity are positive for water oxidation reaction (WOR) and oxygen reduction reaction (ORR) process in hydrogen peroxide (H2O2) generation, respectively. The optimized CQD‐CTF exhibits a high H2O2 generation rate of up to 1036 µmol g−1 h−1 in pure water without any sacrificial agent under visible light, which is 4.6 times than pristine CTF. This work provides a new idea for efficient H2O2 production of organic semiconductors. [ABSTRACT FROM AUTHOR]