Entity: Universitat Rovira i Virgili (URV)
Confidenciality: No
Education area(s): Nanociència, Materials i Processos - Tecnologia Química de Frontera
Title in different languages: A new growth approach to fabricate CuMo alloy nanowires
Abstract: A new growth approach to fabricate CuMo alloy nanowires Cu-Mo alloys are of interest due to their excellent thermal and electrical conductivity, and good fatigue resistance. To date, even though physical (e.g. mechanical alloying, vapor deposition, rapid solidification) and chemical (e.g. co-precipitation, sol-gel) methods have been utilized for Co-Mo film synthesis, few reports have been published for fabricating Cu-Mo films by electrodeposition and none, to the best of the authors’ knowledge as nanowires. Molybdate ions currently cannot be fully reduced in aqueous electrolyte without a codepositing element, referred to as induced codeposition. Typically iron group elements, e.g. Ni, induce best molybdate reduction to zero valence state Mo. Cu has been recognized as also inducing the molybdate reduction reaction, but at a much lower extent. In this work, a new method of combining template electrodeposition and copper displacement reaction was developed for synthesizing Cu-Mo nanowires with a small amount of nickel or iron. Ni-Mo or Fe-Ni-Mo nanowire segments were first electrodeposited into nanopores of polycarbonate membranes, to induce the reduction of molybdate. Next, the membrane was dipped into a low pH copper solution to etch the Ni component, or Fe-Ni component, in the axial direction, and at the same time displace these elements with copper. Nanowires were inspected at different length scales (optical microscopy, SEM and TEM) and the average composition determined by X-ray fluorescence. Results demonstrate that an axial displacement reaction of copper is beneficial for obtaining uniform and integrated Cu-Mo nanowires. Additionally, percentage of Mo in the as-prepared Cu-Mo nanowires can be easily modulated by adjusting the initial Ni-Mo and Fe-Ni-Mo components to reach 20 wt%.
Subject: Enginyeria química
Academic year: 2015-2016
Language: Anglès
Work's public defense date: 2016-08-08
Subject areas: Chemical engineering
Student: Navarrete Gatell, Eric
Department: Enginyeria Química
TFM credits: 12
Creation date in repository: 2017-09-28
Keywords: Nanowires, Molybdenum, Codeposition, Displacement, Copper
Title in original language: A new growth approach to fabricate CuMo alloy nanowires
Project director: Podlaha-Murphy, Elisabeth
Repositori URV