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In this study, the concept of fast SCR for NO reduction with NH as reducing agent is realized via the combination of nonthermal plasma (NTP) with Mn-based catalyst. Experimental results indicate that 10% wt. Mn-Ce-Ni/TiO possesses better physical and chemical properties of surface, resulting in higher NO removal efficiency if compared with 10% wt. Mn-Ce/TiO and 10% wt. Mn-Ce-Cu/TiO. Mn-Ce-Ni/TiO of 10% wt. achieves 100% NO conversion at 150 °C, while 10% wt. Mn-Ce/TiO and 10% wt. Mn-Ce-Cu/TiO need to be operated at a temperature above 200 °C for 100% NO conversion. However, NO conversion achieved with 10% wt. Mn-Ce-Ni/TiO is significantly reduced as HO and SO are introduced into the SCR system simultaneously. Further, two-stage system (SCR with DBD) is compared with the catalyst-alone for NO conversion and N selectivity. The results indicate that 100% NO conversion can be achieved with two-stage system at 100 °C, while N selectivity reaches 80%. Importantly, NO conversion achieved with two-stage system could maintain >95% in the presence of CH, CO, SO, and HO, indicating that two-stage system has better tolerance for complicated gas composition. Overall, this study demonstrates that combining NTP with Mn-based catalyst is effective in reducing NO emission at a low temperature (≤200 °C) and has good potential for industrial application. [ABSTRACT FROM AUTHOR]

WO role in NO reduction over VO-WO/TiO was studied by comparing the kinetic parameters of the selective catalytic reduction (SCR) reaction, the non selective catalytic reduction (NSCR) reaction and the C-O reaction. The results show that the SCR reaction over VO/TiO was promoted after WO incorporation, while the NSCR reaction and the C-O reaction were both restrained. Graphical Abstract: [ABSTRACT FROM AUTHOR]

A novel functional bio-nanocomposite was prepared by deposition of Ag nanoparticles onto the surface of natural eggshell membrane fibers. Practically, the functional groups exposed on the fiber surface can provide locations to anchor Ag ions when immersed into metal precursor solution. The synthesized small-sized Ag nanoparticles with uniform distribution is well decorated on the surface of interwoven fibers of eggshell membrane. The effectiveness of the as-prepared AgNPs/ESM composites as a solid phase heterogeneous catalyst has been evaluated, for the first time, on the well-known 4-nitrophenol reduction to 4-aminophenol in the presence of excess borohydride. Moreover, the kinetics of the reduction reaction was investigated at different temperatures to determine the activation energy. This work provides an important example in the introduction of natural membranes for the fabrication of functional hybrid nanocomposites which could be very useful in varying fields. [ABSTRACT FROM AUTHOR]

A series of cerium-tungsten oxide catalysts was prepared by the co-precipitation method and was evaluated for the selective catalytic reduction of NO by ammonia (NH-SCR) over a wide temperature range. These catalysts were characterized by BET, XRD, XPS and H-TPR analyses. The experimental studies demonstrated that, among cerium-tungsten oxides, CeO-WO with a Ce/W molar ratio of 3/2 exhibited the best activity toward NH-SCR reactions, N selectivity and SO durability over a broad temperature range of 175-500 °C at a space velocity of 47,000 h. The strong interaction between Ce and W could be the main factor leading to the high activity of the CeO-WO mixed oxide catalyst. Graphical Abstract: A series of cerium-tungsten oxide catalysts was prepared by the co-precipitation method and was evaluated for the selective catalytic reduction of NO by ammonia (NH-SCR) over a wide temperature range. These catalysts were characterized by BET, XRD, XPS and H-TPR analyses. The experimental studies demonstrated that, among cerium-tungsten oxides, CeO-WO with a Ce/W molar ratio of 3/2 exhibited the best activity toward NH-SCR reactions, N selectivity and SO durability over a broad temperature range of 175-500 °C at a space velocity of 47,000 h. The strong interaction between Ce and W could be the main factor leading to the high activity of the CeO-WO mixed oxide catalyst.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The catalytic activity of palladium (Pd) nanostructures highly relies on their size and morphology, especially enclosed with high-index facets, which provide more active sites so as to enhance their catalytic performance comparing with their low-index facet counterparts. Herein, Pd concave nanocubes enclosed with {730} facets by a one-pot scalable liquid method, with various high-index facets are synthesized via tuning reduction kinetics. Due to their high-index facets, the Pd concave nanocubes exhibit much higher electrocatalytic activity and stability for methanol oxidation than the Pd nanocubes enclosed by {100} facets and commercial Pd/C. Furthermore, we scale up synthesis of Pd concave nanocubes by expanding the volume of all species to fifty times with high-yield production. [ABSTRACT FROM AUTHOR]