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Gold nanoparticles (AuNPs) with a high specific surface area show efficient activity for the reduction of nitroaromatics. In this study, single-stranded DNA chains (ssDNA, T30, C30 or A30) were used as templates to mediate the formation of AuNPs, and the results demonstrated that the morphologies of the C30-AuNPs or A30-AuNPs had more abundant irregular features than the T30-AuNPs. The catalytic properties and applications of the C30-AuNPs were systematically examined using a reaction model for the reduction of 4-nitrophenol by NaBH4. The effect of different temperatures and pH values on the catalytic activity of C30-AuNPs have been investigated. The C30-AuNPs showed the highest catalytic activity (rate constant kapp = 0.2221 min−1) for the reduction of 4-NP at 35 °C and pH = 7. The conversion of 4-NP to 4-AP using C30-AuNPs followed the Langmuir–Hinshelwood mechanism, which was explained by the principle of promoting electron transfer, i.e. the surface of C30-AuNPs is rich in active sites that promote the process of electron transfer from BH4− to 4-NP, completing the conversion of 4-nitrophenol to 4-aminophenol. Furthermore, the results confirmed that C30-AuNPs were versatile for catalyzing isomers of 4-NP and azo dyes, such as 2-NP, 3-NP, MO, CR and EBT. The results offer new insights into the construction of Au-based catalysts for efficiently removing environmental pollutants. [ABSTRACT FROM AUTHOR]

Prussian blue (PB) and its analogues (PBA) with different structures and adjustable compositions have been recognized as promising materials for catalysis, energy storage, and biological applications. Herein, a simple surface anchoring strategy is proposed to achieve the uniform deposition of CeO2 nanocrystals on the double-cone structure surface of PBA (denoted as Ce@Ce–Fe catalyst) for the selective catalytic reduction of NOx with NH3 (NH3-SCR). Compared with Ce–Fe and Ce@CeO2–Fe2O3, the Ce@Ce–Fe catalyst exhibited the best catalytic activity, widest working temperature window, and highest SO2 tolerance, implying its good application in the process of NH3-SCR. Moreover, the catalysts were characterized systematically to elucidate their surface properties and morphological structure. Taking advantage of the excellent redox performance, unique morphology, mesoporous structure with large surface area and pore diameter, and greater acid content, the Ce@Ce–Fe catalyst exhibited a higher NOx performance. In addition, the Ce@Ce–Fe catalyst also exhibited significant resistance to H2O and SO2 due to its higher content of Fe atoms, implying that Fe plays a critical role in this Ce–Fe based catalytic system. More importantly, the present study indicates that well-dispersed active components and unique architectures can effectively enhance the performance of catalysts. [ABSTRACT FROM AUTHOR]

Prussian blue (PB) and its analogues (PBA) with different structures and adjustable compositions have been recognized as promising materials for catalysis, energy storage, and biological applications. Herein, a simple surface anchoring strategy is proposed to achieve the uniform deposition of CeO2 nanocrystals on the double-cone structure surface of PBA (denoted as Ce@Ce–Fe catalyst) for the selective catalytic reduction of NOx with NH3 (NH3-SCR). Compared with Ce–Fe and Ce@CeO2–Fe2O3, the Ce@Ce–Fe catalyst exhibited the best catalytic activity, widest working temperature window, and highest SO2 tolerance, implying its good application in the process of NH3-SCR. Moreover, the catalysts were characterized systematically to elucidate their surface properties and morphological structure. Taking advantage of the excellent redox performance, unique morphology, mesoporous structure with large surface area and pore diameter, and greater acid content, the Ce@Ce–Fe catalyst exhibited a higher NOx performance. In addition, the Ce@Ce–Fe catalyst also exhibited significant resistance to H2O and SO2 due to its higher content of Fe atoms, implying that Fe plays a critical role in this Ce–Fe based catalytic system. More importantly, the present study indicates that well-dispersed active components and unique architectures can effectively enhance the performance of catalysts. [ABSTRACT FROM AUTHOR]