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Correction for 'Polyaniline nanorods dotted on graphene oxide nanosheets as a novel super adsorbent for Cr(VI)' by Shouwei Zhang et al., Dalton Trans., 2013, 42, 7854-7858, https://doi.org/10.1039/C3DT50149C.

RESUMEN

Retraction of 'Polymer nanodots of graphitic carbon nitride as effective fluorescent probes for the detection of Fe3+ and Cu2+ ions' by Shouwei Zhang et al., Nanoscale, 2014, 6, 4157-4162, DOI: 10.1039/C3NR06744K.

RESUMEN

A novel efficient Ag@AgCl/g-C3N4 plasmonic photocatalyst was synthesized by a rational in situ ion exchange approach between exfoliated g-C3N4 nanosheets with porous 2D morphology and AgNO3. The as-prepared Ag@AgCl-9/g-C3N4 plasmonic photocatalyst exhibited excellent photocatalytic performance under visible light irradiation for rhodamine B degradation with a rate constant of 0.1954 min(-1), which is ∼41.6 and ∼16.8 times higher than those of the g-C3N4 (∼0.0047 min(-1)) and Ag/AgCl (∼0.0116 min(-1)), respectively. The degradation of methylene blue, methyl orange, and colorless phenol further confirmed the broad spectrum photocatalytic degradation abilities of Ag@AgCl-9/g-C3N4. These results suggested that an integration of the synergetic effect of suitable size plasmonic Ag@AgCl and strong coupling effect between the Ag@AgCl nanoparticles and the exfoliated porous g-C3N4 nanosheets was superior for visible-light-responsive and fast separation of photogenerated electron-hole pairs, thus significantly improving the photocatalytic efficiency. This work may provide a novel concept for the rational design of stable and high performance g-C3N4-based plasmonic photocatalysts for unique photochemical reaction.

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Bandgap narrowing and a more positive valence band (VB) potential are generally considered to be effective methods for improving visible-light-driven photocatalysts because of the significant enhancement of visible-light absorption and oxidation ability. Herein, an approach is reported for the synthesis of a novel visible-light-driven high performance polymer photocatalyst based on band structure control and nonmetal and metal ion codoping, that is, C and Fe-codoped as a model, by a simple thermal conversion method. The results indicate that compared to pristine graphitic carbon nitride (g-C3 N4 ), C+Fe-codoped g-C3 N4 shows a narrower bandgap and remarkable positively shifted VB; as a result the light-absorption range was expanded and the oxidation capability was increased. Experimental results show that the catalytic efficiency of C+Fe-codoped g-C3 N4 for photodegradation of rhodamine B (RhB) increased 14 times, compared with pristine g-C3 N4 under visible-light absorption at λ>420 nm. The synergistic enhancement in C+Fe-codoped g-C3 N4 photocatalyst could be attributed to the following features: 1) C+Fe-codoping of g-C3 N4 tuned the bandgap and improved visible-light absorption; 2) the porous lamellar structure and decreased particle size could provide a high surface area and greatly improve photogenerated charge separation and electron transfer; and 3) both increased electrical conductivity and a more positive VB ensured the superior electron-transport property and high oxidation capability. The results imply that a high-performance photocatalyst can be obtained by combining bandgap control and doping modification; this may provide a basic concept for the rational design of high performance polymer photocatalysts with reasonable electronic structures for unique photochemical reaction.

RESUMEN

A simple and green route was developed for the first time to produce fluorescent graphitic carbon nitride (F-g-C3N4) by hydrothermal treatment of bulk g-C3N4. The produced F-g-C3N4 dots have blue emission and a high quantum yield, and were applied as a very effective fluorescent probe for label-free selective and sensitive detection of Cu(2+) and Fe(3+) ions; the limits of detection were as low as 0.5 nM and 1.0 nM, respectively. By using sodium hexametaphosphate (SHPP) as a masking agent of Fe(3+), Cu(2+) was exclusively detected in the presence of Fe(3+) ions. Cu(2+) and Fe(3+) ions in real water samples were also detected successfully. This exceptional fluorescent performance makes the probes based on F-g-C3N4 dots attractive for highly sensitive detection of Cu(2+) and Fe(3+) ions in real water.

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RESUMEN

Water-soluble magnetic-functionalized graphitic carbon nitride (g-C3N4) composites were synthesized successfully by in situ decorating spinel ZnFe2O4 nanoparticles on g-C3N4 sheets (CN-ZnFe) through a one-step solvothermal method. The magnetic properties of CN-ZnFe can be effectively controlled via tuning the coverage density and the size of ZnFe2O4 nanoparticles. The results indicate that the CN-ZnFe exhibits excellent photocatalytic efficiency for methyl orange (MO) and fast separation from aqueous solution by magnet. Interestingly, the catalytic performance of the CN-ZnFe is strongly dependent on the loading of ZnFe2O4. The optimum activity of 160CN-ZnFe photocatalyst is almost 6.4 and 5.6 times higher than those of individual g-C3N4 and ZnFe2O4 toward MO degradation, respectively. By carefully investigating the influence factors, a possible mechanism is proposed and it is believed that the synergistic effect of g-C3N4 and ZnFe2O4, the smaller particle size, and the high solubility in water contribute to the effective electron-hole pairs separation and excellent photocatalytic efficiency. This work could provide new insights that g-C3N4 sheets function as good support to develop highly efficient g-C3N4-based magnetic photocatalysts in environmental pollution cleanup.

RESUMEN

Wide spectral responsive 3D hierarchical CdS/α-Fe2O3 heterojunction nanocomposites were synthesized through a facile chemical bath method under mild conditions, and used for the reduction of Cr(VI) into Cr(III) under visible light irradiation. The effects of CdS/α-Fe2O3 molar ratio in the nanocomposites on the crystal phases, microstructures, optical absorption properties, and photocatalytic reduction of Cr(VI) were investigated comparatively. It was found that the as-synthesized CdS/α-Fe2O3 nanocomposites with a suitable CdS content (e.g., the molar ratio of Fe : Cd = 1.25 : 3) had not only high visible-light-driven photocatalytic activity in the Cr(VI) reduction, but also good photocatalytic stability. The enhanced photocatalytic activity can be ascribed to some CdS nanoparticles closely contacting the α-Fe2O3 microflowers to form a heterojunction structure. These tight heterojunctions of the photocatalysts result in an efficient electron-hole pairs separation at the interface, followed by fast diffusion of photogenerated charge between CdS and α-Fe2O3, which is beneficial for separating the photogenerated carriers in space and improving the photocatalytic activity.

RESUMEN

Hierarchical nanocomposites of polyaniline (PANI) nanorods array on graphene oxide (GO) nanosheets are successfully obtained by dilute polymerization under -20 °C. They exhibit excellent water treatment performance with a superb removal capacity of 1149.4 mg g(-1) for Cr(VI).

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