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The salen–porphyrin based conjugated microporous polymer (SP-CMP) was first constructed by polycondensation reaction of a salen-dialdehyde derivative and pyrrole. Due to the outstanding chemical and thermal stability, abundant micropores with a reasonable pore size, and ordered salen–porphyrin arrays in the A4B4-type polymer framework, the functional CMP was further applied as a Pd nanoparticle support by the coordinate interactions between the polydentate chelating sites with Pd(OAc)2 and subsequent reduction with NaBH4. The as-synthesized composite material (Pd@SP-CMP) was fully characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and solid-state 13C nuclear magnetic resonance (NMR). The porous property of Pd@SP-CMP was also characterized by N2 adsorption/desorption isotherms and the obtained material exhibited a Brunauer–Emmett–Teller (BET) surface area of 266 m2 g−1, together with a pore volume of 0.192 cm3 g−1. The microscopic morphology of Pd@SP-CMP was further evaluated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The Pd@SP-CMP material with highly dispersed Pd nanoparticles exhibited excellent catalytic activity towards Suzuki–Miyaura and Heck–Mizoroki coupling reactions in water or in the dioxane/water mixture. In addition, Pd@SP-CMP also displayed outstanding stability and recyclability, and it can be reused without loss of activity in ten successive reactions. More importantly, the salen–porphyrin based CMPs could be the promising candidates for developing high-performance heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

A series of metal organic frameworks (MOFs) with cobalt, copper and iron as central metal atoms and 1,3,5-benzenetricarboxylic acid as a ligand were synthesized (denoted M-BTC) for selective oxidation of benzyl alcohols. High conversion (92.9%) and good selectivity (97.1%) were achieved over Co-BTC with air as the oxidant. [ABSTRACT FROM AUTHOR]

The activity and stability of CdS for visible-light-driven hydrogen evolution could be significantly enhanced by embedding plasmonic Au nanoparticles. The plasmon resonance energy field of Au nanoparticles could increase the formation rate and lifetime of e−/h+ pairs in CdS semiconductors. [ABSTRACT FROM AUTHOR]

A silica-supported CdS nanoparticle photocatalyst exhibits excellent visible-light driven H2 evolution activity without the use of a cocatalyst. The apparent quantum yield can reach 42% under 420 nm light illumination. [ABSTRACT FROM AUTHOR]

Oxovanadium(iv) and iron(iii) salen complexes grafted onto amino-modified graphene oxide (NH2–GO) have been synthesized via a stepwise procedure and the prepared materials were used as heterogeneous catalysts in the aerobic oxidation of styrene. The structures of these materials have been thoroughly investigated using different characterization techniques such as XRD, N2 adsorption–desorption, TEM, FT-IR, diffuse reflectance UV-visible spectroscopy, ICP-AES, TEM, TG, Raman, and XPS. The results of XRD, N2 adsorption–desorption and TEM revealed that the structures of the prepared catalysts were well preserved. In addition, the results of FT-IR, diffuse reflectance UV-visible spectroscopy, ICP-AES, TG, Raman and XPS suggested that the oxovanadium(iv) and iron(iii) complexes had been incorporated onto amino-modified graphene oxide (GO). It was found that the heterogeneous oxovanadium(iv) catalyst was more active than its homogeneous analogue in the epoxidation of styrene, using acetonitrile as solvent and air as the oxidant in combination with the sacrificial co-reductant isobutyraldehyde, due to site-isolation. Furthermore, the tethered vanadium catalyst was quite stable and could be recycled many times. [ABSTRACT FROM AUTHOR]

Novel graphene oxide (GO) tethered Cu(ii) and Co(ii) salen complexes [M–Salen–GO (M = Cu, Co)] were synthesized via a stepwise procedure and examined as catalysts in the epoxidation of styrene. Acetonitrile was used as a solvent and air as the oxidant in combination with a sacrificial co-reductant isobutyraldehyde. A comparison with homogeneous salen complexes of Co and Cu and graphene oxide (GO) tethered salen complexes was made. Heterogeneous copper(ii) and cobalt(ii) catalysts were confirmed by X-ray diffraction (XRD), FT-IR, diffusion reflection UV-visible spectroscopy, inductively coupled plasma atomic emission spectroscopy (ICP-AES), TEM, TG, Raman and XPS. FT-IR, diffusion reflection UV-visible and inductively coupled plasma atomic emission spectroscopy (ICP-AES), along with TG, Raman and XPS results showed that Cu(ii) and Co(ii) salen complexes were successfully grafted on GO; X-ray diffraction (XRD) and TEM indicated that the sample structures were well preserved. It was found that heterogeneous catalysts were active and showed good recoverability without significant loss in activity and selectivity within successive runs. [ABSTRACT FROM AUTHOR]

A silica-supported CdS nanoparticle photocatalyst exhibits excellent visible-light driven H2 evolution activity without the use of a cocatalyst. The apparent quantum yield can reach 42% under 420 nm light illumination.