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Thepaper deals with oxidation of the biomass-derived model molecule5-(hydroxymethyl)furfural (HMF) catalyzed by the trimetallic mixedoxide RuCo(OH)2CeO2. The catalyst RuCo(OH)2CeO2was prepared through alkali hydrolysis ofRuCl3, Co(NO3)2, and Ce(NO3)2and characterized by X-ray diffraction and transmissionelectron microscopy techniques. RuCo(OH)2CeO2showed high catalytic activity for aerobic oxidation of HMF undermild conditions (in the case of atmospheric oxygen pressure). Variousreaction parameters such as the reaction temperature, catalyst amount,solvent, and oxidant were explored. Results demonstrated that theoxidant and solvent showed a remarkable effect on the aerobic oxidationof HMF to 2,5-diformylfuran (DFF). Under optimal conditions, DFF wasobtained in a high yield of 82.6% with HMF conversion of 96.5% after12 h at 120 °C. More importantly, the catalyst could be reusedseveral times without significant loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

n-Doped small molecular organic thermoelectric materials (OTMs) hold advantages of high Seebeck coefficient and better performance reproducibility over their polymeric analogues; however, high-performance n-type small molecular OTMs are severely lacking. We report here a class of small molecular OTMs based on terminal cyanation of a bithiophene imide-based ladder-type heteroarene BTI2. It was found that the cyanation could effectively lower the lowest unoccupied molecular orbital (LUMO) level from -2.90 eV (BTI2) to -4.14 eV (BTI2-4CN) and thus lead to significantly improved n-doping efficiency. Additionally, terminal cyano-functionalization can maintain the close packing and efficient intermolecular charge transfer between these cyanated molecules, thus yielding high electron mobilities of up to 0.40 cm 2 V -1 s -1 . Benefiting from its low LUMO-enabled efficient n-doping and high electron mobility, an encouraging n-type electrical conductivity of 0.43 S cm -1 and power factor (PF) of 6.34 μW m -1 K -2 were achieved for tetracyanated BTI2-4CN, significantly outperforming those of its noncynated BTI2 (<10 -7 S cm -1 , PF undetectable) and dicyanated BTI2-2CN (0.24 S cm -1 , 1.78 μW m -1 K -2 ). These results suggest the great potential of the terminal cyanation strategy of ladder-type heteroarenes for developing high-performance small molecular OTMs.

Rapid and highly efficient degradation of cured thermoset epoxy resins is a major challenge to scientists. Here, degradable self-cured hyperbranched epoxy resins (DSHE- n , n = 1, 2, and 3) were synthesized by a reaction between 3-isocyanato-4-methyl-epoxy-methylphenylcarbamate and degradable epoxy-ended hyperbranched polyester (DEHP- n ) prepared from maleicanhydride, citric acid, and epichlorohydrin. The chemical structure of DSHE- n was characterized by Fourier transform infrared and 1 H NMR spectra. With an increase in DSHE- n molecular weight, the adhesion strength of self-cured DSHE- n films increases distinctly from class 1 to 4, and their pencil hardness remains about class B-2B. The study on the self-cured behavior and mechanism of DSHE- n shows that the carbamate group of the DSHE- n is decomposed into diamine group to react with epoxy group and form a cross-linked structure. The self-cured DSHE- n films were degraded completely in 2 h at 90 °C in the mixed solution of hydrogen peroxide (H 2 O 2 ) and N , N -dimethylformamide under atmospheric pressure and produced the raw material citric acid, indicating good degradation performance and recyclable property of DSHE- n ., Competing Interests: The authors declare no competing financial interest.