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In general, the polysulfone (PSf) membranes are popular choices for water treatment because they have high thermal stability and good chemical resistance. On the other hand, the filtration capacity of the polysulfone membrane is limited because of its low water flux and poor antifouling ability, which are caused by the low surface hydrophilicity of the membranes. In this research, blending of graphene oxide (GO) or graphene oxide-titanium dioxide (GO-TiO2) mixture into the polysulfone matrix had been carried out through the phase inversion method to enhance the hydrophilic and antifouling properties. Methods such as energy-dispersive X-ray spectroscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, and water contact angle measurement were used to examine the surface properties of the prepared membranes. Experimental results have led to a conclusion that graphene oxide can be stabilized into prepared membranes, and then, by reducing the water contact angle values, the surface of these membranes becomes hydrophilic, which increases the permeability and the water flux of methylene blue from the aqueous feed solution, improving the membrane’s antifouling resistance.

g-C3N4/BaTiO3 composite was hydrothermally synthesized at 200°C for 24 h from a dispersed mixture of g-C3N4 and BaTiO3 in water, in which BaTiO3 was hydrothermally synthesized at 200°C for 48 h using barium nitrate, isopropanol, titanium tetrachloride and sodium hydroxide as precursors without assistance of any surfactant; and graphitic carbon nitride (g-C3N4) was prepared by pyrolysis of melamine at 520°C. The obtained materials were characterized by X-ray diffraction, infrared spectra, scanning electron microscopy, elemental mapping, X-ray photoelectron spectroscopy and ultraviolet–visible diffuse reflectance spectroscopy. The photocatalytic activity of the materials was assessed by degradation of methylene blue (MB) under visible light. The enhancement of photocatalytic activity of the g-C3N4/BaTiO3 composite compared to the single components, g-C3N4 and BaTiO3 was observed, which is attributed to the reduction of combination rate of photogenerated electron–hole pairs in the composite. The MB degradation over the composite was mainly attributed to the photoreduction process induced by the superoxide radical anions (•O2−) and hydroxyl radicals (•OH); and a mechanism was also proposed based on the heterojunction model from the two semiconductor components. [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]

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]

Composites of carbon and WO were successfully synthesized by heating the mixtures of WO and urea at a temperature between 600 and 800 °C in inert atmosphere. The obtained materials were characterized by XRD, SEM, TEM, Raman, XPS, TG-DTA and N adsorption/desorption at 77 K. The results showed that the composites consisted of WO as a main phase which was coated by a thin carbon layer and exhibited a change in shape with heating temperature. The hollow form appeared from the treatment temperature of 700 °C and remained till 900 °C. However, at treatment 900 °C, the WO disappeared and WO formed instead. The adsorption and visible-light photocatalytic degradation of methylene blue on the composites were evaluated. [ABSTRACT FROM AUTHOR]

The mesostructured lamellar phases with the general formula [C nH2 n+1N(CH3)3]3[Fe(CN)6] ( n = 14, 16, 18) were prepared by ion-exchange/precipitation reaction of alkyltrimethylammonium surfactants and K3[Fe(CN)6] complex in aqueous medium. The phases were characterized using powder X-ray diffraction, high-resolution transmission electron microscopy, IR spectroscopy, thermogravimetric, and differential scanning calorimetry means. The results obtained all support a proposed model of crystal structure for these materials, in which the layers are constructed by monolayer of the discrete complex molecules, and the surfactants tails of opposite head groups deeply penetrate and arrange with a tilt angle of 63°. [ABSTRACT FROM AUTHOR]

MoS2/rGO composites were synthesized by hydrothermal method from the precursors of MoS2 and reduced graphene oxide (rGO) prepared in the former steps. The influence of the synthesis conditions including hydrothermal temperature and mass ratio of MoS2 to rGO on the structure, morphology, and optical absorption capacity of the MoS2/rGO composites was systematically investigated using physicochemical characterizations. The photocatalytic performance of as-prepared samples was investigated on the degradation of Rhodamine B under visible light, in which, the composites obtained at hydrothermal temperature of 180°C and MoS2/rGO mass ratio of 4/1 exhibited the highest photodegradation efficiency of approx. 80% after 4 hours of reaction. This enhancement in photocatalytic behaviour of composites could be assigned to the positive effect of rGO in life time expansion of photoinduced electrons—holes. [ABSTRACT FROM AUTHOR]

This study explores the synthesis, characterization, and photocatalytic properties of bismuth metal-organic framework (Bi-MOF) nanorods and their derivatives such as Ag/Bi-MOF and Ag/Bi 2 O 3 . Bi-MOF nanorods exhibit significant photocatalytic activity under visible light, with the addition of silver (Ag) enhancing electron-hole pair separation and reducing their recombination. This leads to improved photocatalytic performance, particularly in the degradation of organic pollutants such as Rhodamine B (RhB) and Methylene Blue (MB). The results show that Bi-MOF and its derivatives demonstrate excellent chemical stability and high performance in photocatalytic applications, even when subjected to high temperatures and tested across a wide pH range. The large surface area and microporous structure facilitate selective adsorption of small organic molecules like MB. The pores and large surface area not only provide numerous active sites but also enhance the interaction between reactants and the catalyst surface, improving photocatalytic efficiency. Bi-MOF and its derivatives perform optimally across a broad pH range, from acidic to alkaline environments, where strong oxidizing hydroxyl radicals (·OH) are easily formed, aiding in the effective degradation of organic compounds. The study also shows that Bi-MOF and its derivatives can be reused multiple times without significant loss in performance. This research contributes to the development of advanced materials for environmental remediation, highlighting the potential of Bi-MOF-based nanocomposites in practical applications., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (This journal is © The Royal Society of Chemistry.)