Phase-pure M1 MoVNbTeOx/TiO2 nanocomposite catalysts: highly catalytic performance for oxidative dehydrogenation of ethane

The catalytic performance of the phase-pure M1 MoVNbTeOx catalyst is enhanced by introducing TiO2 in oxidative dehydrogenation of ethane (ODHE). The space-time yield (STY) of the M1/TiO2 composite catalyst increases...

Synthesis of SDS-Modified Pt/Ti3C2Tx Nanocomposite Catalysts and Electrochemical Performance for Ethanol Oxidation

It is well-known that platinum (Pt) is still the preferred material of anode catalyst in ethanol oxidation, however, the prohibitive high cost and CO poisoning of Pt metal impede the commercialization of fuel cells. Therefore, improving the utilization rate of catalysts and reduce the cost of catalyst become one of the most concerned focus in the construction of fuel cells. In this work, the Pt-based catalysts are synthesized by using different content of sodium dodecyl sulfate (SDS) modified-Ti3C2Tx support, and the dispersion regulation function of SDS modified-Ti3C2Tx supported on Pt nanoparticles is investigated. The structure, composition and morphology of different catalysts are characterized by X-ray diffraction (XRD), X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and high-resolution TEM, respectively. It is found that the Pt nanoparticles in pure Ti3C2Tx surface are serious aggregated and show poor dispersion, whereas the Pt nanoparticles in SDS modified-Ti3C2Tx have a better dispersion. The electrochemical results revealed that SDS modified-Ti3C2Tx supported Pt nanoparticles has higher electrocatalytic activity and stability in both acidic and alkaline ethanol oxidation when the dosage of SDS increases to 100 mg. These findings indicate that the SDS-Ti3C2Tx/Pt catalysts show a promising future of potential applications in fuel cells with modification of Ti3C2Tx support.

Heterogenous Nanocomposite Catalysts With Rhenium Nanostructures for the Catalytic Reduction of 4-nitrophenol

Stable and efficient heterogenous nanocatalysts for the reduction of 4-nitrophenol (4-NP) has attracted much attention in recent years. In this context, a unique and efficient in-situ approach is used for the production of new polymeric nanocomposites (pNCs) containing rhenium nanostructures (ReNSs). These rare materials should facilitate the catalytic decomposition of 4-NP, in turn ensuring increased catalytic activity and stability. These nanomaterials were analyzed using Fourier-Transformation Infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), and X-Ray powder diffraction (XRD). The efficiency of the catalytic reaction was estimated based on the acquired UV-Vis spectra, which enabled the estimation of the catalytic activity using pseud-first order modelling. The applied method resulted in the successful production and efficient loading of ReNSs in the polymeric matrices. Amino functionalities played a primary role in the reduction process. Moreover, the functionality that is derived from 1.1’-carbonyl imidazole improved the availability of the ReNSs, which resulted in 90% conversion of 4-NP with a maximum rate constant of 0.28 min-1 over 11 subsequent catalytic cycles. This effect was observed despite the trace amount of Re in the pNCs (~5%), suggesting a synergistic effect between the polymeric base and the ReNSs-based catalyst.

Construction of ZnO/Keggin Polyoxometalate Nano Heterojunction Catalyst For Efficient Removal of Rhodamine B in Aqueous Solution

In this paper, we synthesized two novel heterojunction nanocomposite catalysts ZnO/Ag4SiW12O40 and ZnO/Cs3PW12O40 by a simple dissolution-precipitation method. The structure and morphology of the samples were analyzed by XRD, TEM, FT-IR, Raman, UV diffuse reflection, XPS and N2 adsorption desorption isotherm. Compared with pure ZnO, the composite catalyst formed with Ag4SiW12O40(AgSiW) and Cs3PW12O40(CsPW) can significantly improve the problem of fast recombination rate of photogenerated carriers in ZnO, and broaden the response range of ZnO to visible light. Rhodamine B (RhB) was used as a simulated pollutant to investigate the photocatalytic degradation performance of the composite catalyst. The experimental results show that the photocatalytic degradation activity of the prepared composite catalyst is much higher than that of pure ZnO, and the degradation performance of ZnO/Ag4SiW12O40 is stronger. Finally, the possible photocatalytic mechanism of ZnO/Ag4SiW12O40 and ZnO/Cs3PW12O40 heterojunction nanocomposite catalysts was proposed by UV diffuse reflection, free radical capture experiment and Mott Schottky test.