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The employment of synchrotron techniques complemented by conventional laboratory systems has allowed us to deepen and improve our knowledge of Roman wall painting procedures. The palette identified in wall paintings from Pompeii and Herculaneum from the second century BC includes goethite, hematite, cinnabar, glauconite, Egyptian blue, and other components such as calcite and aragonite. Proof of the use of organic binders is provided by FTIR and PY-GC/MS. Therefore, the possibility of the use of 'a secco' techniques cannot be ruled out. Pigments in wall paintings are usually found in small percentages and conventional X-ray diffractometers do not detect them. Synchrotron radiation -high-resolution X-ray powder diffraction has allowed identification with only a few micrograms of sample.a rcm_478 286..307

Supported Co catalysts were prepared for sodium borohydride and ammonia borane hydrolysis by magnetron sputtering for the first time under different conditions. Ni foam was selected as support. Deposition conditions (time, pressure, and power) were varied to improve catalytic activity. A decrease in deposition power from 200 to 50 W, leads to a decrease in crystallite and column size and a higher activity of catalysts. The increase in deposition pressure from 1.5x10-2 to 4.5x10-2 mbar produces same effect but in this case the enhancement in activity is higher because amorphous materials were obtained. The highest activity for SB hydrolysis was 2650 ml.min-1 .g cat-1 for the 50W Co 4.5 (4h) sample (E a =60±2 kJ.mol-1). For AB hydrolysis activity for the 50W Co 3.2 (4h) sample was similar. Durability of the thin films was tested for both reactions upon cycling (14 cycles). Diluted acid washing was effective to recover the activity for sodium borohydride reaction but not for ammonia borane hydrolysis. The strong Co-NH 3 interactions explain the non-efficiency of the acid washing.

Highlights• Catalytic hydrogen combustion was studied in a Pt washcoat on SiC foam• The catalyst contains Pt particles of 5-20 nm size on porous Al 2 O 3 with ceria additive • Kinetics was monitored by measuring water concentration through FTIR • The Pt/SiC material shows high thermal stability and reaction start-up at room temperature • Catalyst converted at least 18.5 L H2 .min -1 .g Pt -1 with 35kJ.mol -1 activation energy Abstract A commercial Pt based washcoat, used for catalytic methane combustion, was studied supported on a commercial SiC foam as catalytic material (Pt/SiC) for catalytic hydrogen combustion (CHC). Structural and chemical characterization was performed using Electron Microscopy, X-Ray Diffraction (XRD) and X-Ray Photoelectron Spectroscopy (XPS). The reaction was monitored following water concentration by Fourier Transform Infrared spectra (FTIR). The FTIR method was compared with H2 detection by Gas Cromatography (GC) and has shown to be adequate to study the kinetics of the CHC reaction in steady state under our experimental conditions (very lean 1% (v/v) H2/air mixtures). The catalyst is composed of 5-20 nm disperse Pt nanoparticles decorating a mixture of high surface area Al2O3 and small amounts of ceria supported on the SiC foam which also contains alumina as binder. The Pt/SiC catalytic material has demonstrated to be active enough to start up the reaction in a few seconds at room temperature. The material has been able to convert at least 18.5Lhydrogen.min -1 .gPt -1 at room temperature in conditions of excess of catalyst. The Pt/SiC material was studied after use using XPS and no significant changes on Pt oxidation states were found. The material was characterized from a kinetic point of view. From the conversion-temperature plot a T50 (temperature for 50% conversion) of 34 o C was obtained. Activation energy measured in our conditions was 35±1 kJ.mol -1 .