Anodic selective dissolution of copper alloys in chloride and carbonate melts

The synthesis of materials with a developed electrode surface of the electropositive component of the alloy and a significant near-surface layer was performed by anodic selective dissolution of copper alloys (Cu63–Zn37, Cu40–Zn37, Cu65–Ni35, Cu35–Ni65 and Cu50–Al50). The morphological and electrochemical characteristics of the obtained electrode materials based on mesoporous copper demonstrate its prospects for catalysis substrate application, electrodeposition of materials with specified parameters, and for the low-wear anode base formation. The media was combination of lithium, sodium, potassium carbonates (30 : 30: 40 mol. %), as well as low-melting eutectic mixtures of alkali metal chlorides of various compositions (especially CsCl–KCl–LiCl (54.4 : 15.3: 30.3 wt %) in the temperature range of 623–923 K. The object of the study was copper alloys such as copper-zinc, copper-aluminum, copper-nickel. Anodic selective dissolution was performed under the following electrolysis modes: galvanostatic and potentiostatic modes; rectangular polarization; cyclic voltammetry. The values of geometric current densities were 100, 200, 300, 900, 1400 A/m2. The applied anode potential was +0.1, +0.2 and + 0.5 V (from the open circuit potential of the material). The platinum reference electrode was used. The resulting surface structures were investigated using micro- and X-ray phase analysis. The composition of frozen melt samples after electrolysis completion was studied by atomic absorption analysis. The resulting surface structures were investigated using micro- and X-ray phase analysis. The influence of the following factors on the surface structure of the final anode product was studied and discussed: composition of the studied alloy (the amount of electronegative component in the alloy, as well as its nature); electrolyte composition (chloride and carbonate melt); temperature of selective dissolution (350, 500 and 650°С) It was shown that it is possible to change the nature of the binary alloy dissolution by changing the kinetic parameters (electrolyte composition, temperature), and to obtain a mesoporous material with a developed surface, suitable for heterogeneous catalysis, structural design of electrochemical and electrical devices. a) the most perspective copper-based alloy for the formation of nanoporous and mesoporous materials in salt melts is brass Cu63–Zn37; b) the smallest average pore size had samples of brass Cu63–Zn37 in experiments with chloride melt;