In this article, a method for the synthesis of catalysts for methanol electrooxidation based on additive manufacturing and electroless metal deposition is presented. The research work was divided into two parts. Firstly, coatings were obtained on a flat substrate made of light-hardening resin dedicated to 3D printing. Copper was deposited by catalytic metallization. Then, the deposited Cu coatings were modified by palladium through a galvanic displacement process. The catalytic properties of the obtained coatings were analyzed in a solution of 0.1 M NaOH and 1 M methanol. The influence of the deposition time of copper and palladium on the catalytic properties of the coatings was investigated. Based on these results, the optimal parameters for the deposition were determined. In the second part of the research work, 3D prints with a large specific surface were metallized. The elements were covered with a copper layer and modified by palladium, then chronoamperometric curves were determined. The application of the proposed method could allow for the production of elements with good catalytic properties, complex geometry with a large specific surface area, small volume and low weight.

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One-dimensional (1D) nanostructures, such as nanotubes, nanopores, nanodots and nanocones, are characterized by better catalytic properties than bulk material due to their large active surface area and small geometrical size. These structures can be produced by several methods of synthesis including the one- and two-step methods. In the one-step method, a crystal modifier is added to the solution in order to limit the horizontal direction of structures growing during electrodeposition. In this work, NH4Cl was used as a crystal modifier. Another way of production of 1D nanocones is the electrodeposition of metal in porous anodic alumina oxide (AAO) templates, called the two-step method. In this case, the AAO template was obtained using a two-step anodization process. Nanocones obtained by the two-step method show smaller geometrical size. In this work, cobalt nanoconical structures were obtained from an electrolyte containing CoCl2 and H3BO3. The electrocatalytic properties of materials fabricated by one-step and two-step methods were measured in 1 M NaOH and compared with bulk material electrodeposited from the same electrolyte. There were several microshell structures in the case of Co deposits obtained by the one-step method. To solve this problem, different conditions of synthesis Co cones by the one-step method were applied. The electrocatalytic activity of these samples was checked as well.

nanostructures, such as nanotubes, nanopores, nanodots and nanocones, are characterized by better catalytic properties than bulk material due to their large active surface area and small geometrical size [1]. There are several methods of synthesis these structures, including the one-and two-step methods. In the one-step method, a crystal modifier are added to the solution in order to limit horizontal direction of structures growing during electrodeposition. In this work, cobalt nanoconical structures were obtained from an electrolyte containing CoCl2, H3BO3 and NH4Cl as the crystal modifier. Another way of production of 1D nanocones is electrodeposition of metal into porous anodic alumina oxide (AAO) templates. This method is called the two-step method. In this case, AAO template was obtained using two-step anodization. Then, electrodeposition of cobalt was performed from an electrolyte containing CoSO4 and H3BO3. Nanocones obtained by two-step method shows smaller geometrical size. The bulk sample was electrodeposited from the same electrolyte. The electrocatalytic properties of materials fabricated in one-step and two-step method were measured in 1M NaOH and compared with bulk materials. Co cones obtained by one-step method shows the worst electrocatalytic properties. The hydrogen evolution reaction started the earliest for Co nanocones electrodepsited in the templates.