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A series of covalent organic frameworks (COFs) with β‐ketoenamine linkages named TpTt‐COF, TAPT‐COF, and TpPa‐1 were constructed for photocatalytic H2O2 generation in pure water and ambient air under visible light. Among them, TpTt‐COF performed striking H2O2 yield of 2647 μmol L−1, which is 3.5, 17.5, and 176.5‐fold those of TAPT‐COF, TpPa‐1, and bulk g‐C3N4, respectively, attributing to the electron‐deficient trait, short charge diffusion distance, and the narrowest bandgap of TpTt‐COF. Additionally, to achieve the facile recovery, TpTt‐COF was firmly and evenly anchored on melamine sponges (MS) because plenty of amino groups on the surface of MS could be involved in the β‐ketoenamine formation and guide the synthesis of TpTt‐COF on MS. The corresponding H2O2 evolution over this photocatalyst monolith is also respectable and can be well repeated at least four times. This work is quite instructive for photocatalyst construction based on covalent organic frameworks and facile photocatalytic applications. [ABSTRACT FROM AUTHOR]

Cellulose‐derived carbon (CC) dot‐directed growth of ZnIn2S4 was achieved through hydrothermal treatment of carboxylated cellulose followed by in situ growth of ZnIn2S4 nanosheets. The carbon dots inherited from carboxylated cellulose equip plenty of surface carboxyl groups, which induce the ionic interaction with Zn2+ and In3+ and the guided growth of ZnIn2S4. As a result, the nanosheets of ZnIn2S4 are evenly and intimately grown on the small carbon dots, providing high‐speed channels for charges transfer. In conjunction with the reinforced visible‐light capture and good conductivity of carbon dots, the resultant CC/ZnIn2S4 shows an outstanding photocatalytic activity. As a proof‐of‐concept, visible‐light‐driven 5‐hydroxymethylfurfural oxidation into 2,5‐diformylfuran was conducted. The evolution of 2,5‐diformylfuran over the optimal CC/ZnIn2S4 sample can reach ∼2980 μmol g−1, about 3.4 times that of pristine ZnIn2S4. Additionally, the apparent quantum yield could attain 3.4 % at a wavelength of 400 nm. [ABSTRACT FROM AUTHOR]

Metal-organic framework derived materials received a lot of attention due to their significant benefits in photocatalytic reactions. In this work, a Z-scheme ZnIn 2 S 4 /Bi 2 S 3 hierarchical heterojunction is first developed by a one-pot method using CAU-17 as a template. The specific preparation method endows an intimate interface contact between these two monomers, and CAU-17-derived Bi 2 S 3 possesses a high surface area and porosity, resulting in an efficient charge separation and O 2 capture. Thus, for photocatalytic H 2 O 2 production from the O 2 reduction reaction, the ZnIn 2 S 4 /Bi 2 S 3 heterojunction can achieve an H 2 O 2 yield of 995 µmol L -1 in pure water and ambient air under visible light, 4.5 and 4 times that of ZnIn 2 S 4 and Bi 2 S 3 , respectively. In addition, in tetracycline solution, ZnIn 2 S 4 /Bi 2 S 3 can degrade tetracycline with a degradation rate of 95% by photocatalysis, and at the same time, a final H 2 O 2 production yield of 1223 µmol L -1 is reached. Similarly, high yields of H 2 O 2 are also obtained from wastewater containing o-nitrophenol, acid golden yellow, or acid red, and these pollutants are effectively degraded. This work reveals the potential of metal-organic framework-derived materials in photocatalysis, as well as provides insights into H 2 O 2 green synthesis and wastewater treatment., (© 2024 Wiley‐VCH GmbH.)

Cellulose-derived carbon (CC) dot-directed growth of ZnIn 2 S 4 was achieved through hydrothermal treatment of carboxylated cellulose followed by in situ growth of ZnIn 2 S 4 nanosheets. The carbon dots inherited from carboxylated cellulose equip plenty of surface carboxyl groups, which induce the ionic interaction with Zn 2+ and In 3+ and the guided growth of ZnIn 2 S 4 . As a result, the nanosheets of ZnIn 2 S 4 are evenly and intimately grown on the small carbon dots, providing high-speed channels for charges transfer. In conjunction with the reinforced visible-light capture and good conductivity of carbon dots, the resultant CC/ZnIn 2 S 4 shows an outstanding photocatalytic activity. As a proof-of-concept, visible-light-driven 5-hydroxymethylfurfural oxidation into 2,5-diformylfuran was conducted. The evolution of 2,5-diformylfuran over the optimal CC/ZnIn 2 S 4 sample can reach ∼2980 μmol g -1 , about 3.4 times that of pristine ZnIn 2 S 4 . Additionally, the apparent quantum yield could attain 3.4 % at a wavelength of 400 nm., (© 2022 Wiley-VCH GmbH.)