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[EN] The hydrogenation activity and physico-chemical characterization of a series of NiMo catalyst supported on materials with different acid-base properties (Al2O3, layered double hydroxides-derived MgAl oxides and MgO) have been investigated. The results show a clear correlation between the electrodonor capacity of the support, the negative charge density of the supported NiMo oxides and the intrinsic hydrogenation rate of the sulfided phase. Spectroscopic characterization ruled out any possible contribution derived from differences in the NiMoS2 stack or slab size distributions, as determined by high-resolution transmission electron microscopy. The experimental results obtained suggest the occurrence of an electron transfer phenomena from the support to the supported NiMoS2 slabs, being this effect stronger for supports with higher electrodonor capacity. This work presents a specific electronic support effect that goes beyond the classical dispersing and stabilizing role. ; This work has been supported by ExxonMobil Research and Engi-neering and by the Spanish Government through RTI2018-101033-B-I00 (MCIU/AEI/FEDER, UE) . We thank the Electron Microscopy Service of the UPV for their help in sample characterization. ; López-Cruz, C.; Guzman, J.; Cao, G.; Martínez, C.; Corma Canós, A. (2021). Modifying the catalytic properties of hydrotreating NiMo-S phases by changing the electrodonor capacity of the support. Catalysis Today. 382:130-141. https://doi.org/10.1016/j.cattod.2021.08.002 ; S ; 130 ; 141 ; 382

The hydrogenation activity and physico-chemical characterization of a series of NiMo catalyst supported on materials with different acid-base properties (AlO, layered double hydroxides-derived MgAl oxides and MgO) have been investigated. The results show a clear correlation between the electrodonor capacity of the support, the negative charge density of the supported NiMo oxides and the intrinsic hydrogenation rate of the sulfided phase. Spectroscopic characterization ruled out any possible contribution derived from differences in the NiMoS stack or slab size distributions, as determined by high-resolution transmission electron microscopy. The experimental results obtained suggest the occurrence of an electron transfer phenomena from the support to the supported NiMoS slabs, being this effect stronger for supports with higher electrodonor capacity. This work presents a specific electronic support effect that goes beyond the classical dispersing and stabilizing role. ; This work has been supported by ExxonMobil Research and Engineering and by the Spanish Government through RTI2018-101033-B-I00 (MCIU/AEI/FEDER, UE). We thank the Electron Microscopy Service of the UPV for their help in sample characterization.

We report the encapsulation of platinum species in highly siliceous chabazite (CHA) crystallized in the presence of N,N,N-trimethyl-1-adamantammonium and a thiol-stabilized Pt complex. When compared to Pt/SiO2 or Pt-containing Al-rich zeolites, the materials in this work show enhanced stability toward metal sintering in a variety of industrial conditions, including H2, O2, and H2O. Remarkably, temperatures in the range 650–750 °C can be reached without significant sintering of the noble metal. Detailed structural determinations by X-ray absorption spectroscopy and aberration-corrected high-angle annular dark-field scanning transmission electron microscopy demonstrate subtle control of the supported metal structures from ∼1 nm nanoparticles to site-isolated single Pt atoms via reversible interconversion of one species into another in reducing and oxidizing atmospheres. The combined used of microscopy and spectroscopy is critical to understand these surface-mediated transformations. When tested in hydrogenation reactions, Pt/CHA converts ethylene (∼80%) but not propylene under identical conditions, in contrast to Pt/SiO2, which converts both at similar rates. These differences are attributed to the negligible diffusivity of propylene through the small-pore zeolite and provide final evidence of the metal encapsulation. ; This work has been supported by the European Union through the SYNCATMATCH project (Grant Agreement No. 671093) and the Spanish Government through "Severo Ochoa Program" (SEV 2012-0267) and MAT2015-71261-R. This research used beamline 9-BM of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. ; Peer Reviewed

[EN] We report the encapsulation of platinum species in highly siliceous chabazite (CHA) crystallized in the presence of N,N,N-trimethyl-1-adamantammonium and a thiol-stabilized Pt complex. When compared to Pt/SiO2 or Pt-containing Al-rich zeolites, the materials in this work show enhanced stability toward metal sintering in a variety of industrial conditions, including H-2, O-2, and H2O. Remarkably, temperatures in the range 650-750 degrees C can be reached without significant sintering of the noble metal. Detailed structural determinations by X-ray absorption spectroscopy and aberration-corrected high-angle annular dark-field scanning transmission electron microscopy demonstrate subtle control of the supported metal structures from similar to 1 nm nanoparticles to site-isolated single Pt atoms via reversible interconversion of one species into another in reducing and oxidizing atmospheres. The combined used of microscopy and spectroscopy is critical to understand these surface-mediated transformations. When tested in hydrogenation reactions, Pt/CHA converts ethylene (similar to 80%) but not propylene under identical conditions, in contrast to Pt/SiO2, which converts both at similar rates. These differences are attributed to the negligible diffusivity of propylene through the small-pore zeolite and provide final evidence of the metal encapsulation. ; This work has been supported by the European Union through the SYNCATMATCH project (Grant Agreement No. 671093) and the Spanish Government through "Severo Ochoa Program" (SEV 2012-0267) and MAT2015-71261-R. This research used beamline 9-BM of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. We thank Isabel Millet and Paul Stevens for technical assistance, and Randall Meyer, Aaron Sattler, and Dave Marler for review ...

BACKGROUND: Increasingly, there has been recognition that siloed approaches focusing mainly on human health are ineffective for global antimicrobial resistance (AMR) containment efforts. The inherent complexities of AMR containment warrant a coordinated multisectoral approach. However, how to institutionalize a country's multisectoral coordination across sectors and between departments used to working in silos is an ongoing challenge. This paper describes the technical approach used by a donor-funded program to strengthen multisectoral coordination on AMR in 11 countries as part of their efforts to advance the objectives of the Global Health Security Agenda and discusses some of the challenges and lessons learned. METHODS: The program conducted a rapid situational analysis of the Global Health Security Agenda and AMR landscape in each country and worked with the governments to identify the gaps, priorities, and potential activities in multisectoral coordination on AMR. Using the World Health Organization (WHO) Joint External Evaluation tool and the WHO Benchmarks for International Health Regulations (2005) Capacities as principal guidance, we worked with countries to achieve key milestones in enhancing effective multisectoral coordination on AMR. RESULTS: The program's interventions led to the achievement of key benchmarks recommended actions, including the finalization of national action plans on AMR and tools to guide their implementation; strengthening the leadership, governance, and oversight capabilities of multisectoral governance structures; establishing and improving the functions of technical working groups on infection prevention and control and antimicrobial stewardship; and coordinating AMR activities within and across sectors. CONCLUSION: A lot of learning still needs to be done to identify best practices for building mutual trust and adequately balancing the priorities of individual ministries with cross-cutting issues. Nevertheless, this paper provides some practical ideas for countries and ...