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Using a facile refluxing synthesis, a series of BiO(ClBr)0.5−x/2Ix solid solutions was prepared and applied as photocatalysts for the degradation of organic pollutants. The synthesized solid solutions crystallized in microspheres are constructed by nanoplates which transform into nanosheets for increasing iodine ions contents. Furthermore, introducing iodine ions significantly decreased the optical bandgap of the obtained solid solutions. The photocatalytic activity of these samples over the degradation of Rhodamine B indicates the highest performance of the solid‐solution at x=0.2 with a decomposition efficiency of 92.6 % for 120 mins of reaction under the light emission diode (LED) irradiation which is much higher than that of pure sample and BiOCl0.5Br0.5. This enhancement in photocatalytic performance was attributed to the effective separation of photo‐induced electron‐hole pairs. [ABSTRACT FROM AUTHOR]

Summary: Despite being established as the most popular commercial energy storage system (ESS), lithium‐ion batteries (LIBs) are still facing practical issues due to their high cost and limited availability of the lithium source. Sodium‐ion batteries (SIBs), which have economic and environmental costs, but on‐par performance compared to LIBs, are now being considered as the next‐generation ESS. Herein, we report a facile and mass‐scalable synthesis of SnS2 nanosheets grafting on porous g‐C3N4 via direct solid‐state reaction from tin (IV) acetate and thiourea as precursors. The synthesized SnS2@g‐C3N4 composites served as an anode active material for SIBs with outstanding performances in terms of high capacity and ultralong cycling stability. The optimum anode delivered an initial discharge capacity of 1350.7 mAh g−1 and the first coulombic efficiency of 55.13%. However, this composite can offer a remarkable charge capacity of 919.6 and 602.7 mAh g−1 after 400 and 3000 cycles at specific currents of 500 and 2000 mA g−1, respectively. The enhancement in the cyclability of the obtained composites is attributed to the presence of g‐C3N4 as a scaffolding material effectively relieving serious strains induced by the volume variation of SnS2 during sodium storage. The high exfoliation of SnS2 nanosheets with larger interlayer spacing as well as the presence of a self‐induced internal electric field formed at the heterointerface of SnS2 and g‐C3N4 enables the enhanced transport of electrons and sodium ions, accompanied by the improvement in their electrochemical performance. [ABSTRACT FROM AUTHOR]

The n%Mn-MoS2/rGO (labeled as n%MMS/rGO, where n% = Mn/(Mn + Mo) in mol) composites were successfully prepared by a facile hydrothermal method from the Mn-MoS2 (MMS) and rGO precursors, in which the MMS was obtained by a facile one-step calcination of (NH4)6Mo7O24·4H2O, (NH2)2CS, and Mn(CH3COO)2·4H2O as precursors in N2 gas at 650°C. The samples were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron paramagnetic resonance spectroscopy (EPR), UV-visible diffuse reflectance spectroscopy (UV-Vis DRS), and X-ray photoelectron spectroscopy (XPS), which indicates the composites containing nanosheets of Mn-MoS2 and rGO components. The photocatalytic activities of the n%MMS/rGO composite photocatalysts were evaluated through the photodegradation of rhodamine B (RhB) under the visible light irradiation. The enhancement in the photocatalytic performance of the achieved composites was attributed to the synergic effect of Mn doping and rGO matrix. The investigation of photocatalytic mechanism was also conducted. [ABSTRACT FROM AUTHOR]

A MoS2/g‐C3N4 composite was synthesized by a significantly simple method using Na2MoO4 and thiourea as precursors, without the need for a hydrothermal or an ultrasound step. The photocatalytic activity of the synthesized material was evaluated by the degradation of rhodamine B (RhB) in aqueous solution under blue light. The composites with low content of MoS2 performed better than pure g‐C3N4. Using a low‐power light‐emitting diode light source, an improvement of two orders of magnitude in the photochemical space‐time yield was achieved, proving enhanced energy efficiency and productivity compared to earlier studies. The degradation pathway of organic pollutants was confirmed by the effects of selective scavengers. [ABSTRACT FROM AUTHOR]

Visible‐light‐driven photocatalysis has received considerable attention in the environmental treatment in recent years. In this paper, WS2/g‐C3N4 composite photocatalysts with various contents of WS2 and g‐C3N4 were synthesized by a facile method via heating the mixtures of tungstic acid and thiourea, and denoted as nWCN, where n is weight ratio of thiourea to tungstic acid. The composites were characterized by XRD, SEM, EDS, TEM, IR, Raman spectroscopy, XPS, TGA, and UV–vis DRS. The characterizations reveal that the composites contain WS2 nanosheets coated by g‐C3N4 and the relative content of WS2 in the composites decreases with increasing amount of thiourea in the reaction mixtures. All the composites exhibited the better photocatalytic activity in degradation of methylene blue in aqueous solution than the single components, WS2, and g‐C3N4. Among them, 7WCN sample performed the highest activity. A synergistic effect between WS2 and g‐C3N4 in photocatalytic activity for the composites was observed. [ABSTRACT FROM AUTHOR]

A theoretical study of the CH···N hydrogen bond in the interactions of trihalomethanes CHX3 (X = F, Cl, Br) with ammonia and its halogen derivatives NH2Y (Y = F, Cl, Br) has been carried out thoroughly. The complexes are quite stable, and their stability increases in going from CHF3 to CHCl3 then to CHBr3 when Y keeps unchanged. With the same CHX3 proton donor, enhancement of the gas phase basicity of NH2Y strengthens stability of the CHX3···NH2Y complex. The CH···N hydrogen bond strength is directly proportional to the increase of proton affinity (PA) at N site of NH2Y and the decrease of deprotonation enthalpy (DPE) of CH bond in CHX3. The CHF3 primarily appears to favor blue shift while the red-shift is referred to the CHBr3. The blue- or red-shift of CHCl3 strongly depends on PA at N site of NH2Y. We suggest the ratio of DPE/PA as a factor to predict which type of hydrogen bond is observed upon complexation. The SAPT2+ results show that all CH···N interactions in the complexes are electrostatically driven regardless of the type of hydrogen bond, between 48% and 61% of the total attractive energy, and partly contributed by both induction and dispersion energies. [ABSTRACT FROM AUTHOR]

The synthesis of reduced graphene oxide modified by magnetic iron oxide (Fe3O4/rGO) and its application for heavy metals removal were demonstrated. The obtained samples were characterized by X-ray diffraction (XRD), nitrogen adsorption/desorption isotherms, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT-IR), and magnetic measurement. The results showed that the obtained graphene oxide (GO) contains a small part of initial graphite as well as reduced oxide graphene. GO exhibits very high surface area in comparison with initial graphite. The morphology of Fe3O4/rGO consists of very fine spherical iron nanooxide particles in nanoscale. The formal kinetics and adsorption isotherms of As(V), Ni(II), and Pb(II) over obtained Fe3O4/rGO have been investigated. Fe3O4/rGO exhibits excellent heavy metal ions adsorption indicating that it is a potential adsorbent for water sources contaminated by heavy metals. [ABSTRACT FROM AUTHOR]