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Porous triazine‐/heptazine‐based carbon nitride (THCN) homojunction with chloride (Cl) doping was synthesized by a simple, one‐step photochemical synthesis route for efficient visible‐light‐driven overall water splitting. The phase ratio of triazine‐based carbon nitride (TCN) and heptazine‐based carbon nitride (HCN), texture and morphology of the THCN isotype junction were finely tuned by varying ultraviolet irradiation time and washing solvents. After washing with acetonitrile, the resulting porous THCN nanosheets with 48 h irradiation contain 21 wt % TCN and 79 wt % HCN units and reveal a significantly improved photocatalytic performance with H2 and O2 production rates up to 7.9 and 4.2 μmol h−1, respectively, about 3.8 times higher than that of THCN prepared by 36 h illumination. The dual‐phase interaction, holey structure, and Cl dopants favor the exposure of active sites, extended visible‐light harvesting, accelerated charge transfer, and enhanced photoreduction ability, thereby improving photocatalytic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] A subtle flower-like MIL-125-NH 2 @BiOI was fabricated by a facile solvothermal method for simultaneously eliminating Cr(VI)/tetracycline mixed pollutants under visible light. The strong interaction between amino in MIL-125-NH 2 and Bi3+ of BiOI promotes the formation of this unique inlaid structure and enables the favorable contact between MIL-125-NH 2 and BiOI, thus accelerating the transfer of charge carriers. Remarkably, MIL-125-NH 2 @BiOI displays a superior activity compared with that of two monomers for the photocatalytic reduction of Cr(VI) and degradation of tetracycline. More significantly, the photocatalytic efficiency can be further boosted in the coexistence of Cr(VI) and tetracycline, which is 1.8 and 1.6 times that of single Cr(VI) and tetracycline, respectively. The synergistic effect between Cr(VI) reduction and tetracycline oxidative degradation can further facilitate the separation of photo-induced electrons and holes, resulting in the improved efficiencies in the Cr(VI)/tetracycline coexistent environment. This work sheds light on that MOF-based photocatalysts possess huge potential for practical environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] Pancake-like TiO 2 (M-TiO 2) derived from the metal-organic framework was inlaid into three-dimensional flower-like BiOI through a facile solvothermal method. M-TiO 2 supplies large surface area and mesoporous structure for attachment and transfer of the substrates and products, while BiOI acts as a photosensitizer to absorb visible light and generates electrons and holes. The distinct structure of M-TiO 2 /BiOI gives a favorable contact between the two monomers, and promotes the transfer of charge carriers. In conjunction with the proper band positions of M-TiO 2 and BiOI, the efficient separation of electron-hole pairs is attained. Benefiting from the above cooperative effects of M-TiO 2 and BiOI, the performance for the vanillin generation from sodium lignosulfonate (SLS) over M-TiO 2 /BiOI composites has a prominent improvement under visible light. Specifically, the yield over optimal M-TiO 2 /BiOI sample is about 5.8 mg/g SLS , obviously superior to that over pristine M-TiO 2 (~1 mg/g SLS) and BiOI (~1.1 mg/g SLS). It is found that h+ and O 2 – play the key role for vanillin generation from sodium lignosulfonate, and the low vanillin generation under UV–vis light sheds light on that OH is an adverse factor. We hoped that this work could inspire the studies on the photocatalytic valorization of biomass using noble metal-free catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxygen vacancies-rich Bi 2 MoO 6 nanoflakes were facilely anchored on MIL-121. • The oxygen vacancies can highly accelerate the charges transfer and separation. • Vo-BMO/M is more efficient than Bi 2 MoO 6 , MIL-121 and Bi 2 MoO 6 /MIL-121. • Vo-BMO/M can efficiently photocatalytic removal of mixed Cr(VI)/2-nitrophenol. Oxygen vacancy-rich Bi 2 MoO 6 nanoflakes were uniformly anchored on cuboid MIL-121 via benign solvothermal and thermal-reduction methods. Benefiting from the efficient light capture and rich electron traps triggered by oxygen vacancies, intimate interface contact and intrinsic heterostructure, the enhanced separation and transportation rates of photo-induced charge carriers are achieved. Consequently, Bi 2 MoO 6 /MIL-121 with rich oxygen vacancies performs excellent photocatalytic activities, which are 4.8, 7.1, 1.4 times higher for Cr(VI) reduction, and 6.1, 5.4, 1.2 times higher for 2-nitrophenol degradation compared with those of Bi 2 MoO 6 , MIL-121 and Bi 2 MoO 6 /MIL-121 without oxygen-vacancies, respectively. Furthermore, thanks to the timely consumption of photo-induced electrons and holes by Cr(VI) reduction and 2-nitrophenol degradation, respectively, the corresponding photocatalytic efficiencies are further boosted in their coexistent environment. This work would enlighten the design of metal-organic framework-based (photo)catalysts for the treatment of complicated pollution. [ABSTRACT FROM AUTHOR]

MIL-101(Cr)@ZnIn 2 S 4 hierarchical heterojunction was delicately designed and fabricated through the in-situ growth of ZnIn 2 S 4 on MIL-101 and electrostatic self-assembly. It is affirmed that the Cr–S interface bonding between MIL-101 and ZnIn 2 S 4 in their composite was established based on the characterization results of X-ray photoelectron spectroscopy, Raman and zeta potential. Thus, a high-speed channel for charges transfer is offered due to the Cr–S bond, intimate interface contact and hierarchical structure of MIL-101@ZnIn 2 S 4 , which largely inhibits the recombination of photo-induced charge carriers and promises a remarkable photocatalytic activity. Choosing visible-light-driven reduction of Cr(VI) as a model, the optimal MIL-101@ZnIn 2 S 4 sample can reduce 95% of Cr(VI) within 30 min, corresponding to a rate constant of 0.107 min−1, which is 2.9-fold compared with blank ZnIn 2 S 4 counterpart (MIL-101 has a negligible performance). Additionally, a conspicuous apparent quantum yield of 9.7% can be achieved at a wavelength of 420 nm. Eventually, to reinforce the practicability of MIL-101@ZnIn 2 S 4 , the composite powders were manufactured as aerogels utilizing bacterial cellulose as a substrate. The MIL-101@ZnIn 2 S 4 aerogel still exerts an enviable performance for photocatalytic reduction of Cr(VI) and stability. This work could inspire the material design and environmental remediation based on MOFs. [Display omitted] • MIL-101@ZnIn 2 S 4 hierarchical heterojunction with Cr–S bonds was delicately designed. • A high-speed channel for charges transfer is presented over MIL-101@ZnIn 2 S 4. • Efficiently photocatalytic reduction of Cr(VI) is achieved over MIL-101@ZnIn 2 S 4. • Aerogel was prepared from powder to improve the practicability of MIL-101@ZnIn 2 S 4. [ABSTRACT FROM AUTHOR]

• Bi 2 S 3 /BiOCl@ZnIn 2 S 4 composite with Bi 2 S 3 as transition layer was constructed. • Bi 2 S 3 /BiOCl@ZnIn 2 S 4 shows high activities on Cr(VI) photocatalytic reduction. • The efficiency is 3.3 and 24.1 times as high as that of ZnIn 2 S 4 and Bi 2 S 3 /BiOCl. • The intimate heterostructure causes the boosted photocatalytic activity. Delicate construction based on 2D epitaxial heterostructure can be an effective route to adequately excavate and utilize its superiorities. Here, a core-shell Bi 2 S 3 /BiOCl@ZnIn 2 S 4 hierarchical heterostructure is rationally designed and built by Bi 2 S 3 epitaxial growth on two-dimensional template-like BiOCl and ZnIn 2 S 4 nanosheets in-situ growth. The epitaxial growth of Bi 2 S 3 on BiOCl endows the tight contact between them. More importantly, Bi 2 S 3 as the interlayer could offer an extra intimate junction to ZnIn 2 S 4 due to the chemical interaction of S2− between Bi 2 S 3 and ZnIn 2 S 4. Such a Bi 2 S 3 /BiOCl@ZnIn 2 S 4 composite was explored for visible-light-driven reduction of Cr(VI), and much satisfactory performance was achieved, which is about 3.3 and 24.1-fold increase compared to that of ZnIn 2 S 4 and Bi 2 S 3 /BiOCl respectively. Efficient generation, separation and transfer of photo-generated charge carriers inherited from this ternary hierarchical composite made significant contributions to the highly elevated photocatalytic activity. This work may stimulate the construction of multiple hierarchical composites based on 2D epitaxial heterostructure material for efficient photocatalysis or other optoelectronics. [ABSTRACT FROM AUTHOR]

• Cd x Zn 1-x S/ZnO nanocomposites were readily fabricated via a facile one-pot method. • The Cd/Zn molar ratios were tuned by altering the amounts of Na 2 S and Na 2 S 2 O 3. • Cd x Zn 1-x S/ZnO showed glorious performance on photocatalytic reduction of Cr(VI). • Cd 0.68 Zn 0.32 S/ZnO nanoparticles have tiny diameters of about 5−8 nm. Cd x Zn 1-x S/ZnO nanohybrids were fabricated by using mixed Na 2 S and Na 2 S 2 O 3 as the sulfur source via a facile one-pot synthesis. Cd x Zn 1-x S/ZnO with x = 0.54, 0.58, 0.62, 0.68 and 0.75 was successfully tuned by altering the molar ratio of Na 2 S and Na 2 S 2 O 3. Sole sulfur source Na 2 S or Na 2 S 2 O 3 could only generate Cd 0.5 Zn 0.5 S or CdS/ZnO, respectively. The in-situ co-growth of Cd x Zn 1-x S and ZnO makes them combine penetratingly in Cd x Zn 1-x S/ZnO nanohybrids, giving them a highly intimate contact. The natural matched band-edge positions and highly intimate contacts between Cd x Zn 1-x S and ZnO are conductive to charge separation and transfer. Benefiting from the structural and compositional merits, the optimized Cd x Zn 1-x S/ZnO nanohybrid with sizes of about 5−8 nm exhibited outstanding performance for Cr(VI) reduction under visible-light illumination. The newly designed one-pot synthetic strategy in this work may provide a brand-new pathway in developing high-efficiency multi-component photocatalysts for practical use. [ABSTRACT FROM AUTHOR]