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[Display omitted] • A core-satellite MOF-on-MOF hybrid was designed and synthesized. • Independent intelligent release for multi-agrochemicals was achieved. • The UV resistances of dinotefuran and tebuconazole were 7.0 and 1.9 times higher. • The toxicity of MOF-on-MOF hybrid on zebrafish was 2.3 times lesser. Intelligent delivery formulations of agrochemicals have had a great impact on improving utilization efficiency, reducing chemical usage and easing the risk on the environment. However, constructing smart carriers for multi-agrochemicals to simultaneously control multiple botanic diseases, remains a challenge. In this study, a core-satellite MOF-on-MOF hybrid was designed for intelligent pest and fungus management. Zirconium-based metal–organic framework (UIO) nanoparticles were synthesized as metal–organic framework (MOF) cores to load the insecticide dinotefuran (DNF). Subsequently, a fungicide tebuconazole (Teb) loaded zeolitic imidazolate framework (ZIF) was formed in situ as MOF satellites. The loading contents of DNF and Teb were 6.87% and 8.59%, respectively. DNF released rapidly under alkaline conditions corresponding to the microenvironment of pests, whereas Teb released preferentially under acidic environment. The EC 95 of the MOF-on-MOF hybrid against Exserohilum turcicum was 3.5 times lower than that of Teb alone. After 48 h, the mortality of armyworm treated with 3.0 mg/L MOF-on-MOF hybrid was 87%. The UV resistances of DNF and Teb were 7.0 and 1.9 times higher, respectively, than that of the free pesticides. This work provides a facile technology for precise delivery of multi-agrochemicals, holding substantial promise for sustainable agriculture. [ABSTRACT FROM AUTHOR]

In this work, a 2D hybrid CdS nanosheets(NSs)/MoS 2 layered heterojunctions were successfully synthesized by a two-step hydrothermal method and subsequent ultrasonic treatment. The results showed that the loading ultrathin MoS 2 NSs as co-catalysts could significantly boost the photocatalytic H 2 -evolution activity of CdS NSs. It is demonstrated that the optimized 2D CdS NSs/MoS 2 (1.0 wt%) layered heterojunctions could achieve the highest photocatalytic H 2 -evolution activity of 1.75 mmol g −1 h −1 from an aqueous solution containing sulfide and sulfite under visible light, which is 2.03 times as high as that of the pristine CdS NSs. It is believed that the deposition of ultrathin MoS 2 NSs and intimate 2D–2D coupling interfaces are mainly responsible for the excellent H 2 -evolution performance of 2D CdS NSs/MoS 2 layered heterojunctions, owing to the effectively promoted separation and transportation of charge carriers and the enhanced following surface H 2 -evolution kinetics. Interestingly, the lactic acid and formic acid have also been demonstrated to be better sacrificial reagents than the Na 2 S/Na 2 SO 3 , for the photocatalytic H 2 evolution over the 2D CdS NSs/MoS 2 layered heterojunctions. It is hoped that the strategy of 2D–2D interfacical coupling based on CdS NSs can become a general strategy to improve the H 2 -evolution activity over various kinds of conventional semiconductor NSs. [ABSTRACT FROM AUTHOR]

Due to their unique physicochemical, optical and electrical properties, 2D semimetallic or semiconducting graphene has been extensively utilized to construct highly efficient heterojunction photocatalysts for driving a variety of redox reactions under proper light irradiation. In this review, we carefully addressed the fundamental mechanism of heterogeneous photocatalysis, fundamental properties and advantages of graphene in photocatalysis, and classification and comparison of graphene-based heterojunction photocatalysts. Subsequently, we thoroughly highlighted and discussed various graphene-based heterojunction photocatalysts, including Schottky junctions, Type-II heterojunctions, Z-scheme heterojunctions, Van der Waals heterostructures, in plane heterojunctions and multicomponent heterojunctions. Several important photocatalytic applications, such as photocatalytic water splitting (H 2 evolution and overall water splitting), degradation of pollutants, carbon dioxide reduction and bacteria disinfection, are also summarized. Through reviewing the important advances on this topic, it may inspire some new ideas for exploiting highly effective graphene-based heterojunction photocatalysts for a number of applications in photocatlysis and other fields, such as photovoltaic, (photo)electrocatalysis, lithium battery, fuel cell, supercapacitor and adsorption separation. [ABSTRACT FROM AUTHOR]

In this report, g-C 3 N 4 -based photocatalysts with dual co-catalysts of amorphous NiS and carbon black were firstly synthesized through a facile two-step process. The g-C 3 N 4 /carbon black/NiS composite photocatalyst were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet–visible spectroscopy (UV–vis), N 2 adsorption, photoluminescence (PL) spectra and transient photocurrent responses. The photocatalytic activities for photocatalytic hydrogen evolution under visible light irradiation ( λ ≥ 420 nm) were measured using an aqueous solution containing triethanolamine as an electron donor. Moreover, the results showed that the ternary g-C 3 N 4 photocatalyst loaded by 0.5 wt% carbon black and 1.5 wt% NiS could achieve the highest H 2 -production rate of 992 μmol g −1 h −1 under visible-light irradiation (>420 nm), which is about 2.51 times higher than that of the corresponding binary g-C 3 N 4 /1.5% NiS photocatalyst. It is believed that the enhanced photocatalytic H 2 -evolution activities could be attributed to the excellent synergetic effect between the carbon black and NiS as co-catalysts on the surface of g-C 3 N 4 , leading to the improved visible light absorption, promoted charge separation and enhanced the following H 2 -evolution kinetics. This work would not only demonstrate the promising potentials of carbon black as co-catalyst for applications in visible-light H 2 generation, but also offer a new insight into the construction of highly efficient and stable g-C 3 N 4 -based hybrid semiconductor nanocomposites with dual co-catalysts for diverse photocatalytic applications. [ABSTRACT FROM AUTHOR]