The Chemistry of Transition Metal Carbides and Nitrides

4.2.4 Electron-probe microanalysis.- 4.3 Results and discussion.- 4.3.1 Phase equilibria.- 4.3.2 Carbon and nitrogen diffusivities.- 4.4 Conclusion.- Acknowledgments.- Reference.- Theory.- 5 The origins of the similarities between late transition metals and early transition metal monocarbides.- Abstract.- 5.1 Introduction.- 5.2 Bonding of the B1 monocarbides.- 5.3 Bonding of fcc metals.- 5.4 Band structures of the monocarbides.- 5.5 Conclusion.- Acknowledgments.- References.- 6 Fermi surface of hexagonal tungsten carbide.- Abstract.- 6.1 Introduction.- 6.2 Experimental.- 6.3 Results and discussion.- 6.3.1 Low-temperature magnetoresistance.- 6.3.2 de Haas-van Alphen data.- 6.3.3 Experimental Fermi surfaces.- 6.4 Conclusions.- Acknowledgements.- References.- 7 Orbital symmetry and superconductivity in carbides and borocarbides.- Abstract.- 7.1 Introduction.- 7.1.1 Summary of computational approaches.- 7.1.2 Boron vs. carbon.- 7.1.3 Molecular orbital analysis of diatomic and triatomic fragment.- 7.2 Superconductivity and the isolobal analogy.- 7.2.1 Electronic structure of dicarbides.- 7.2.2 Electronic structure of borocarbides.- 7.2.3 The isolobal analogy.- 7.2.4 Transition temperatures.- Acknowledgments.- References.- New Materials.- 8 Recent developments in ternary nitride chemistry.- Abstract.- 8.1 Introduction.- 8.2 Synthesis of ternary and quaternary nitrides.- 8.3 Lithium-containing ternary and quaternary nitrides.- 8.4 Other alkali metal-containing ternary nitrides.- 8.5 Alkaline earth-containing ternary nitrides.- 8.6 Transition metal ternary nitrides.- 8.7 Properties.- 8.8 Conclusions.- Acknowledgment.- References.- 9 Transition metal-based double nitrides.- Abstract.- 9.1 Introduction.- 9.2 High-pressure synthesis of (Nb1?xMx)N(M = Al, Ga, In) solid solution.- 9.3 New ternary nitrides between alkaline earth and 3d-transition metals.- 9.3.1 The new compound SrNiN and the (Ca1?xSrx)NiN (0 ? X ? 0.5) solid solution with [Ni-N]2? infinite chain.- 9.3.2 The new compound Ca3CoN3 with a trigonal planar [CON3]6? anion.- 9.4 Rf-sputter deposition of metastable metal nitrides and their solid solutions.- 9.5 Conclusion.- References.- 10 Magnetic properties of rare earth-iron compounds containing carbon and/or nitrogen.- Abstract.- 10.1 Introduction.- 10.2 Crystallography and magnetism.- 10.3 Experimental.- 10.3.1 Materials.- 10.3.2 Plasma reactions.- 10.3.3 Ball-milling.- 10.3.4 High-pressure sintering.- 10.3.5 Zinc metal addition.- 10.3.6 Characterization.- 10.4 Results and discussion.- 10.4.1 Addition effect of Co and C on Sm2Fe17.- 10.4.2 Plasma nitriding and carbonitriding.- 10.4.3 Grinding of Sm2Fe17Xy.- 10.4.4 High-pressure sintering of Sm2Fe17Xy.- 10.5 Conclusions.- Acknowledgments.- References.- Synthesis.- 11 The synthesis of titanium nitride and titanium carbonitride by self-propagating combustion.- Abstract.- 11.1 Introduction.- 11.2 Experimental.- 11.3 Results.- 11.4 Discussion.- 11.5 Conclusion.- References.- 12 Combustion synthesis of transition metal nitrides.- Abstract.- 12.1 Combustion synthesis of transition metal nitrides: an overview.- 12.2 Experimental.- 12.2.1 Reactor assembly.- 12.2.2 Chemicals, experimental procedure and characterization.- 12.3 Combustion of transition metals in nitrogen: experimental observations.- 12.3.1 Melting and the effect of solid phase dilution on conversion.- 12.3.2 Effect of nitrogen pressure on combustion characteristics.- 12.3.3 Effect of metal particle size and morphology.- 12.4 Summary.- References.- 13 New route to molybdenum nitrides and oxynitrides: preparation and characterization of new phases.- Abstract.- 13.1 Introduction.- 13.2 Cubic ?-Mo2N type oxynitride phase.- 13.2.1 Synthesis conditions.- 13.2.2 Chemical analysis.- 13.2.3 X-ray and neutron diffraction analysis.- 13.2.4 Powder aging and regeneration.- 13.2.5 Long time nitriding.- 13.2.6 Orthorhombic distortion of the cubic phase.- 13.3 New ?-Mo2C type molybdenum nitride modification.- 13.3.1 Introduction.- 13.3.2 Experimental.- 13.3.3 Results and discussion.- 13.4 Hexagonal ?-MoN type nitride phases.- 13.4.1 Introduction.- 13.4.2 A new method of preparing nitrides by using sulphides.- 13.4.3 Results and discussion.- 13.4.4 High surf ace area MoS2 precursor.- 13.5 Conclusion.- References.- 14 Synthesis of thin films of Cr, Mo and W carbides and nitrides.- Abstract.- 14.1 Introduction.- 14.2 Experimental.- 14.3 Results and discussion.- 14.3.1 Phase formation.- 14.3.2 Purity of the films.- 14.3.3 Orientation of the films.- 14.3.4 Ordered phases.- 14.4 Conclusion.- Acknowledgments.- References.- 15 Single-source precursors for the chemical vapor deposition of titanium and vanadium carbide and nitride.- Abstract.- 15.1 Introduction.- 15.2 Guidelines for the design of the precursors.- 15.3 Experimental section.- 15.4 Study with the Ti-C-N system.- 15.4.1 Precursors to titanium carbide.- 15.4.2 Precursors to titanium nitride.- 15.5 Study within the V-C-N system.- 15.5.1 Precursors to vanadium carbide.- 15.5.2 Precursors to vanadium nitride.- 15.6 Conclusion.- Acknowledgments.- References.- Catalysis.- 16 Carbides of transition metals as catalysts for oxidation reactions.- Abstract.- 16.1 Introduction.- 16.2 Carbide catalysts and their characterization.- 16.2.1 Materials.- 16.2.2 Heats of oxygen adsorption.- 16.2.3 Influence of adsorbed oxygen on carbide work functions.- 16.3 Oxidation of hydrogen.- 16.3.1 Catalysis under excess oxygen.- 16.3.2 Catalysis under excess hydrogen.- 16.4 Oxidation of carbon monoxide.- 16.5 Oxidation of ammonia.- 16.6 Carbides-NO2interaction.- 16.7 Oxidative coupling of methane.- 16.8 Conclusions.- Acknowledgments.- References.- 17 Surface molybdenum species and acid sites on nitrided moly bdena-alumina catalysts.- Abstract.- 17.1 Introduction.- 17.2 Experimental.- 17.2.1 Reagents and catalyst.- 17.2.2 Catalyst preparation.- 17.2.3 Characterization.- 17.3 Results and discussion.- 17.3.1 Surface composition and surface species.- 17.3.2 Surface acidity.- 17.3.3 The nature of acid sites.- 17.3.4 Surface active sites.- 17.4 Conclusions.- Acknowledgements.- References.- 18 Carbide-oxide interactions in bulk and supported tungsten carbide catalysts for alcohol synthesis.- Abstract.- 18.1 Introduction.- 18.2 Experimental.- 18.3 Results.- 18.3.1 Bulk tungsten carbide.- 18.3.2 Supported tungsten carbide.- 18.4 Discussion.- 18.4.1 Bulk tungsten carbide.- 18.4.2 Supported tungsten carbide.- 18.5 Conclusion.- References.- 19 Fischer-Tropsch synthesis and XRD characterization of an iron carbide catalyst synthesized by laser pyrolysis.- Abstract.- 19.1 Introduction.- 19.2 Experimental.- 19.3 Results and discussion.- 19.3.1 Activity.- 19.3.2 Characterization.- 19.4 Conclusions.- Acknowledgments.- References.- 20 Study of the isomerization of C6 and C6+ alkanes over molybdenum oxycarbide catalysts.- Abstract.- 20.1 Introduction.- 20.1.1 Catalyst and process development.- 20.1.2 New carbide catalysts.- 20.2 Experimental.- 20.2.1 Materials and catalyst preparation.- 20.2.2 Catalyst testing apparatus and product analysis.- 20.2.3 Characterization techniques.- 20.3 Results.- 20.3.1 C6-C8 alkane isomerization at atmospheric pressure.- 20.3.2 Effect of pressure on the isomerization of n-heptane and n-octane.- 20.3.3 Isomerization selectivity at high conversion.- 20.4 Discussion.- 20.5 Conclusion.- Acknowledgments.- References.- 21 Characterization of oxygen-treated carbides of molybdenum and tungsten for n-hexane-dihydrogen reactions.- Abstract.- 21.1 Introduction.- 21.2 Experimental.- 21.3 Results.- 21.3.1 n-Hexane-H2 reactions.- 21.3.2 Catalyst characterization.- 21.4 Discussion.- 21.5 Conclusions.- Acknowledgment.- References.- 22 Synthesis and catalytic properties of tungsten carbide for isomerization, reforming and hydrogenation.- Abstract.- 22.1 Introduction.- 22.2 Experimental.- 22.2.1 Preparation of unsupported tungsten carbide, W2C.- 22.2.2 Preparation of W2C/SiC/Al2O3.- 22.2.3 Preparation of W2C/zeolite Y.- 22.2.4 Catalyst evaluation.- 22.3 Results and discussion.- 22.3.1 Carbide synthesis.- 22.3.2 n-Heptane isomerization over unsupported W2C.- 22.3.3 Sulfur resistance of W2C.- 22.3.4 n-Heptane reforming over W2C/SiC/Al2O3.- 22.3.5 Thiophene hydrodesulfurization over unsupported W2C.- 22.3.6 Thiophene hydrogenation over W2C/zeolite Y.- 22.3.7 Acetonitrile hydrogenation over W2C/zeolite Y.- 22.4 Conclusions.- Acknowledgments.- References.- Spectroscopy and Microscopy.- 23 Chemisorption of CO and NO molybdenum carbide foils.- Abstract.- 23.1 Introduction.- 23.2 Experimental.- 23.3 Results.- 23.3.1 Sample activation.- 23.3.2 Chemisorption of CO and NO.- 23.4 Discussion.- 23.5 Conclusions.- Acknowledgment.- References.- 24 Characterization of the electronic and catalytic properties of vanadium carbide: a comparative study of VC/V(110) model surfaces and VC powder materials.- Abstract.- 24.1 Introduction.- 24.2 Experimental methods.- 24.3 Results and discussion.- 24.3.1 Preparation and characterization of VC/V(110) model surfaces.- 24.3.2 NEXAFS characterization of VC powder catalysts.- 24.3.3 Comparison of VC/V(110) with VC powder catalysts: a case study of the dehydrogenation of iso-butane on vanadium carbide.- 24.4 Conclusions.- Acknowledgments.- References.- 25 Surface shifts in core level energies of transition metal carbides and nitrides.- Abstract.- 25.1 Introduction.- 25.2 Surface core level shifts.- 25.2.1 Experimental surface shifts in metal and nonmetal levels.- 25.2.2 Estimates of surface core level shifts.- 25.3 Some application examples.- 25.4 Summary.- References.- 26 Study of the Auger metal peak of carbides and nitrides by factor analysis.- Abstract.- 26.1 Introduction.- 26.2 Theoretical considerations.- 26.2.1 Shape of the Auger peaks.- 26.2.2 Factor analysis applied to AES.- 26.3 Experimental.- 26.3.1 Preparation of the samples.- 26.3.2 Auger analysis.- 26.4 Results.- 26.4.1 W2N/W.- 26.4.2 ?-WC1?x/W.- 26.4.3 Bulk tungsten carbide.- 26.5 Discussion.- 26.5.1 Interpretation of the experimental data.- 26.5.2 The factor analysis method.- 26.6 Conclusion.- Acknowledgments.- References.- 27 Transition metal nitride and carbide nanoparticles.- Abstract.- 27.1 Introduction.- 27.2 Preparation of nitrides and carbides of Fe, Mo and W by CO2 laser pyrolysis.- 27.3 General properties of nanoscale carbides and nitrides of Fe, Mo and W.- 27.3.1 Fe carbide and nitride nanoparticles.- 27.3.2 Mo and W carbide and nitride nanoparticles.- 27.4 Structural characterization.- 27.4.1 X-ray diffraction.- 27.4.2 High resolution transmission electron microscopy (HR-TEM) studies.- 27.4.3 Chemical composition and surface characterization.- 27.5 Catalytic properties.- 27.5.1 Fe carbides.- 27.5.2 Catalytic activity of Mo2NxOy and Mo2CxOy for heteroatom removal.- 27.6 Conclusions.- Acknowledgments.- References.- 28 Carbide formation during activation of iron Fisher-Tropsch catalysts.- Abstract.- 28.1 Introduction.- 28.2 Experimental.- 28.3 Results.- 28.3.1 FT synthesis activity.- 28.3.2 Catalyst characterization.- 28.3.3 Sample microstructure after activation.- 28.3.4 Sample microstructure after activation and 10 h reaction.- 28.3.5 Sample microstructure after activation and 45 h reaction.- 28.3.6 XPS analysis.- 28.4 Discussion.- 28.4.1 The role of activation.- 28.4.2 The role of the carbide in F-T synthesis.- 28.5 Conclusions.- Acknowledgements.- References.- Indexes.