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Owing to the synergetic effect of high photo-thermo transformation efficiency and improved charge separation, the Cs 3 Bi 2 Br 9 /MoS 2 S-scheme heterojunction exhibits excellent photothermocatalytic CO 2 reduction performance without any extra heat input. [Display omitted] Photothermocatalytic CO 2 reduction has been considered as a green and sustainable strategy for solar-to-fuel conversion, since it can utilize the solar energy to simultaneously provide heat input and produce photogenerated charge carriers. To this end, exploring photothermal catalysts with broad-band absorption, high photo-heat conversion and charge separation efficiency is highly desirable. In this work, an innovative Cs 3 Bi 2 Br 9 /MoS 2 (CBB/MoS 2) composite has been elaborately constructed to investigate the photothermocatalytic performance towards CO 2 reduction. In this composite, MoS 2 plays dual roles: with photoinduced self-heating effect, it can act as an extra heater to accelerate the catalytic reaction, and meanwhile serves as a cocatalyst to promote charge separation by forming S-scheme heterojunction with CBB. As expected, the developed CBB/MoS 2 composite delivered outstanding photothermocatalytic activity for CO 2 reduction without any extra heat input, with the CO production rate reaching 172.79 μmol g−1h−1. As confirmed by experimental tests and theoretical calculations, the superior photothermocatalytic CO 2 reduction performance of CBB/MoS 2 was attributed to the synergetic effect of high photo-thermo transformation efficiency and highly improved charge separation. The present work offers a potential strategy for developing highly-efficient photothermal catalysts used in artificial photosynthesis. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Sb O V O Mo chain is newly formed on VMoTi after the Sb loading. • Sb/VMoTi exhibits a wide synergic temperature window for NO x and CB elimination. • CB oxidation over Sb/VMoTi follows the Mars–van–Krevelen mechanism and Eley–Rideal mechanism. • The promotion mechanism of CB oxidation over VMoTi by Sb loading is discovered. Chlorobenzene (CB) oxidation using commercial selective catalytic reduction catalysts as a co-benefit of nitrogen oxides (NO x) elimination in terms of the synergic temperature window and polychlorinated byproducts formation was unsatisfactory. Herein, antimony (Sb) was loaded onto V 2 O 5 -MoO 3 /TiO 2 (VMoTi) to enhance its performance for CB oxidation as a co-benefit of NO x elimination, and the promotion mechanism of CB oxidation by Sb loading was investigated. CB oxidation rates of VMoTi and Sb/VMoTi relied on their oxidizing abilities and their numbers of V5+ ions, adsorbed CB, gaseous CB, lattice oxygen, and adsorbed oxygen. A newly formed Sb O V O Mo chain was observed on VMoTi after Sb loading, resulting in a modest enhancement of oxidizing ability and a slight increase in the numbers of lattice oxygen and adsorbed oxygen. Moreover, more Brønsted acid sites were formed on VMoTi after Sb loading, which facilitated CB adsorption and Cl species removal as HCl. Hence, Sb loading not only significantly enhanced the CB oxidation activity of VMoTi, thereby expanding the synergistic temperature window for NO x and CB elimination, but also effectively inhibited the formation of polychlorinated byproducts. Therefore, Sb/VMoTi was a promising catalyst for chlorinated volatile organic compounds oxidation as a co-benefit of NO x elimination. [ABSTRACT FROM AUTHOR]

It is a great challenge for vehicles to satisfy the increasingly stringent emission regulations for pollutants and greenhouse gases. Throughout the history of the development of vehicle emission control technology, catalysts have always been in the core position of vehicle aftertreatment. Aiming to address the significant demand for synergistic control of pollutants and greenhouse gases from vehicles, this review provides a panoramic view of emission control technologies and key aftertreatment catalysts for vehicles using fossil fuels (gasoline, diesel, and natural gas) and carbon-neutral fuels (hydrogen, ammonia, and green alcohols). Special attention will be given to the research advancements in catalysts, including three-way catalysts (TWCs), NOx selective catalytic reduction (SCR) catalysts, NOx storage-reduction (NSR) catalysts, diesel oxidation catalysts (DOCs), soot oxidation catalysts, ammonia slip catalysts (ASCs), methane oxidation catalysts (MOCs), N2O abatement catalysts (DeN2O), passive NOx adsorbers (PNAs), and cold start catalysts (CSCs). The main challenges for industrial applications of these catalysts, such as insufficient low-temperature activity, product selectivity, hydrothermal stability, and poisoning resistance, will be examined. In addition, the future development of synergistic control of vehicle pollutants and greenhouse gases will be discussed from a catalysis perspective. [ABSTRACT FROM AUTHOR]

Two new hexanuclear copper (II) complexes, [Cu6(G2hexpyD)(DMF)24](TFA)12 and [Cu6(G2hexbzaD)(DMF)18](TFA)12, where G2hexpyD and G2hexbzaD are second-generation dendrimers (G = 2) and TFA is trifluoroacetate, have been synthesized. The prepared copper (II) complexes have been fully characterized. Furthermore, to prepare dendrimer encapsulated copper nanoparticles (G2dendrimer-CuNPs), metal ions were chemically reduced by NaBH4 in 2-methoxyethanol, which yielded zero-valent metal particles with a narrow size distribution. The catalytic reduction of para-nitrophenol to para-aminophenol by G2dendrimer-CuNPs was evaluated in the presence of NaBH4. The reduction reaction was completed in 3 min. The reaction progress was monitored by electronic absorption spectroscopy. The rate constant was calculated to be 0.0073 and 0.0079 s−1 for G2hexbzaD-CuNPs and G2hexpyD-CuNPs, respectively. The results revealed that G2dendrimer-CuNPs exhibit high catalytic performance in the conversion of para-nitrophenol to para-aminophenol. Easy separation, low price, high recyclability and great efficiency are the main advantages of G2dendrimer-CuNPs that make them as the suitable catalysts for the catalytic reduction of para-nitrophenol. [ABSTRACT FROM AUTHOR]

In order to meet the increasingly stringent emission regulations for NOx in the exhaust gas of engines, selective catalytic reduction (SCR) technology is extensively studied and practiced. The key to this technology is the catalyst utilized in the chemical reactions of SCR. It is required to develop the SCR catalyst with good low-temperature performance and a wide active temperature window. A series of Cerium-based metal oxides TiCemWrO2−δ synthesized by solution combustion synthesis is studied in this paper. The SCR activity test was used to select the catalyst with the best performance. The NO conversion rate of the best catalyst in our studies reached 80% at 150 °C, kept 100% from 200 °C to 420 °C and the N2 selectivity remained above 95% for 100–500 °C. The SO2 resistance test was carried out at 250 °C and proved that our catalyst had good SO2 resistance. During the test, the NO conversion rate slightly decreased while 100 ppm SO2 was injected, but it remained above 80% for 24 h. The NO conversion rate recovered to the original value when the SO2 supply was cut off. The N2 selectivity remained at 100% throughout the process. Catalysts were characterized using BET, XRD, and SEM methods. In-situ DRIFTS method was used to study the reaction mechanism of the TiCe0.2W0.2O2−δ catalyst. It showed that the NH4+ species absorbed on the Brønsted acid played a dominant role in the SCR reactions. The bridge nitrate resulted from the NO absorption and gas phase NO was involved in the reaction. In conclusion, the mechanism studied included two routes of L-H and E-R. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chlorella@Mn catalyst had excellent resistance to alkali/alkaline earth metal poisoning. • P O Mn site could be used as a sacrificial site to bind to the alkali/alkaline earth metals. • Chlorella@Mn catalyst surface S, P and Si elements were bound to K, Na, Ca and Mg elements. • Poisoning effects of alkali/alkaline earth metals on Chlorella@Mn had been determined. • NH 3 -SCR reaction mechanism in the presence of alkali/alkaline earth metals was determined. In the selective catalytic reduction of NOx by NH 3 (NH 3 -SCR), conventional Mn-based denitration catalysts often suffered from susceptibility to poisoning by alkali and alkaline earth metals, this paper presented an innovative self-protected Chlorella@Mn denitration catalyst. Remarkably, in the presence of high concentrations (2 wt%) of alkali and alkaline earth metal oxides, the Chlorella@Mn catalyst sustained a NOx conversion exceeding 96 % at 175 °C. At an even higher concentration (4 wt%), NOx conversion above 90 % at 175 °C, surface analysis revealed that P O Mn sites acted as sacrificial sites, binding to the alkali and alkaline earth metals, the Chlorella@Mn catalyst surface naturally carried a spectrum of acidic species (such as SO 4 2−, PO 3 −, SiO 3 2−), proficient in capturing alkali/alkaline earth metal effectively, elements such as S, P, and Si formed bonds with K, Na, Ca, and Mg. The synergistic protection of the active sites and the surface elements avoided the deactivation of the catalyst. The detrimental effects of high concentrations of alkali and alkaline earth metals were primarily due to promoting an excessively high valence state of Mn on the catalyst surface and the reduction or loss of NH 3 adsorption and activation at Brønsted acid sites. This research provided valuable insights for advancing the development of low-temperature denitration catalysts with improved resistance to alkali and alkaline earth metal poisoning. [ABSTRACT FROM AUTHOR]