In this communication, we report a general strategy for the production of carbon nanodots (CDs) by microwave irradiation of amino acids in the presence of acid or alkali. The resultant CDs exhibit strong photoluminescence and intense chemiluminescence enhancement of the NaIO(4)-H(2)O(2) system.

Covalent triazine-based frameworks (CTFs) with a graphene-like layered morphology have been controllably synthesized by the trifluoromethanesulfonic acid-catalyzed nitrile trimerization reactions at room temperature via selecting different monomers. Platinum nanoparticles are well dispersed in CTF-T1, which is ascribed to the synergistic effects of the coordination of triazine moieties and the nanoscale confinement effect of CTFs. CTF-T1 exhibits excellent photocatalytic activity and stability for H2 evolution in the presence of platinum under visible light irradiation (λ ≥ 420 nm). The activity and stability of CTF-T1 are comparable to those of g-C3 N4 . Importantly, as a result of the tailorable electronic and spatial structures of CTFs that can be achieved through the judicial selection of monomers, CTFs not only show great potential as organic semiconductor for photocatalysis but also may provide a molecular-level understanding of the inherent heterogeneous photocatalysis.

Porous ZnIn2S4 microspheres have been successfully synthesized by means of a facile thermal solution method at 353 K. This method was a simple route that involved low temperature, no templates, no catalysts, no surfactants, or organic solvents. Scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, nitrogen sorption analysis, and a UV-vis spectrophotometer were used to characterize the products. The results demonstrated that the microspheres, which were composed of many ZnIn2S4 single crystal nanosheets, underwent the Oswald ripening and self-assembly processes. A morphology formation mechanism has been proposed and discussed. The porous ZnIn2S4 product showed an enhancing visible-light photocatalytic activity for methyl orange degradation. The as-grown architectures may have potential applications in solar energy conversion, environmental remediation, and advanced optical/electric nanodevices.

Sulfur-doped covalent organic frameworks were synthesized via a simple approach for enhanced photocatalytic hydrogen evolution from water under visible light.

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Nanocrystal Zn x Cd1−x S solid solutions were successfully and simply prepared by hydrothermal processes using stable, less toxic, inorganic salts Cd(Ac)2, Zn(Ac)2, and Na2S as the reactants. The band gap of the solid solutions can be tuned by changing constituent stoichiometries of Cd and Zn. With the increase of Cd molar fraction, the X-ray diffraction peaks of the Zn x Cd1−x S nanocrystals gradually shifted to small angle. Using photocatalytic degradation of methyl orange as model reactions in the aqueous phase under visible light irradiation (λ > 420 nm), the samples prepared at the condition (Cd/Zn = 3:1, 160 °C, 16 h) possessed the best activity. The diameter of the particles was about 15 nm. Transmission electron microscopy showed the particles were spherical and homogeneous. The photocatalytic conversion was up to 96% and was obviously superior to CdS and TiO2−x N x degradation under identical conditions. Liquid chromatogram/mass spectrometery was used to test the degradation products. X-ray photoelectron spectroscopy detected the valence state of elements in the samples before and after the degradation. At the same time, their degradation of p-hydroxyazobenzene, rhodamine B, and congo red also achieved good effect.

The nanocrystal In 2 S 3 (nc-In 2 S 3 ) has been used as a visible light active photocatalyst. The optical absorption indicated a narrow band gap (E g )1.9 eV) for nc-In 2 S 3 . Compared with TiO 2-x N x , the decomposition of methyl orange using nc-In 2 S 3 revealed enormously enhanced visible light activity. The • OH during the photocatalytic degradation process was detected by terephthalic acid photoluminescence probing technique (TA-PL). The organic intermediate products were successfully separated by liquid chromatogram and subsequently identified by an electrospray ionization (ESI) mass spectral technique. The possible photocatalytic mechanism is presented.

Zn x Cd 1-x S nanorods were successfully synthesized by microwave method. Characterized by transmission electron microscopy, Zn x Cd 1-x S samples were composed of a large quantity of homogeneous rods with diameter about 10 nm. The photocatalytic degradation of methyl orange (MO) in the aqueous phase under visible light irradiation (420 nm < λ < 800 nm) was taken as a model reaction. The conversion of MO degradation using Zn 0.28 Cd 0.72 S as the photocatalyst was up to 96% after 6 h of irradiation. The separation and identification of degradation products were measured by liquid chromatography mass spectroscopy (LC-MS). After 6 h of irradiation, the intensity of the main absorption peak of MO (m/z ) 304) descended in mass spectrum view, while some new peaks of degradation products showed up. From these results of LC-MS analysis, it can be concluded that it was really a photocatalytic degradation process.