III International Conference

PP-III-14ELECTROCHEMICAL SYNTHESIS OF Mo 2 C CATALYTICAL COATINGS INMOLTEN SALTSKuznetsov S.A., Dubrovskiy A.R., Rebrov E.V. 1 , Schouten J.C. 1Institute of Chemistry, Kola Science Centre RAS, Apatity, Murmansk region, Russia1 Laboratory of Chemical Reactor Engineering, Eindhoven University of Technology, 5600MB Eindhoven, The NetherlandsE-mail: kuznet@chemy.kolasc.net.ruThe aim of this study is the development of new generations of highly active and stablecatalytic coatings for the water gas shift (WGS) reaction by application of high-temperatureelectrochemical synthesis in molten salts. Three different methods and electrolytes were usedfor electrosynthesis of molybdenum carbide in the present investigation.Electrochemical synthesis of molybdenum carbides from molten salts offers considerableadvantages over other methods. For example, electrochemical methods such as Pulse Platingand Reversed Plating provide a possibility to control the structure and phase composition, thethickness of the coatings, the grain size (down to nanomaterials), porosity, smoothness, andthe texture of the layer. The other advantages are: (i) relatively low synthesis temperature(973-1123 K); (ii) parameters of electrochemical depositions can be easily adapted in scalingupsynthesis; (iii) the method can be applied to the substrates with a complicated geometry(such as microstructured plates) for obtaining of uniform coatings with respect to thickness,grain size and composition of the layer; (iv) high purity of resulting coatings even with lowgradeinitial reactants; (v) the production costs are much lower comparing to other methods.Electrochemical synthesis of molybdenum carbide coatings on molybdenum substratewas performed by galvanostatic electrolysis with utilization of the next molten salts systems:NaCl-KCl-Li 2 CO 3 (1); NaCl-KCl-Na 2 MoO 4 -Li 2 CO 3 (2); LiCl-KCl-Li 2 C 2 (3).Alkali chlorides (Prolabo, 99.5 wt.%) were dehydrated by continuous and progressiveheating just above the melting point in a gaseous HCl atmosphere in quartz ampoules. Theexcess of HCl was removed from the melt by an argon flow. The salts were handled in aglove box and stored in sealed glass ampoules. Li 2 CO 3 (chemically pure) and Na 2 MoO 4 ⋅2H 2 O(chemically pure) were dried for 24 h at 473 K. Li 2 C 2 was synthesized in situ in LiCl-KCleutectic melt by discharge of Li + cations at the graphite cathode with cathodic current density2 A cm -2 . Alkali chlorides were mixed in a required ratio, placed in a glassy carbon ampoule(SU-2000 type) and transferred to a sealed stainless steel retort. The latter was evacuated to a494