Electrodeposition of transition metal sulfides and phosphides on 3D electrodes for water splitting

Abstract

This project will study the use of additive manufacturing (3D printing) to obtain electrodes modified with Ni, Co, and/or Mo phosphides and sulfides to be used for hydrogen production by water electrolysis. The 3D printing will be used to manufacture electrodes from conductor-PLA by Fused Deposition Modeling (FDM) using different geometries and pore sizes. Thereby, the influence of these parameters on the ohmic drop and on the detachment of bubbles of the electrode at high reaction overpotential will be evaluated. Modification with Ni, Co, and/or Mo sulfides and phosphides will be carried out in two methods. The first will be by electrodeposition of metallic phosphides and sulfides on the electrode obtained by FDM using electrolytes containing the precursors. The second will be the incorporation of metallic phosphides and sulfides synthesized by the hydrothermal method in the ink for 3D printing by Direct Ink Writing (DIW) method. The electrodes will be characterized by SEM, DRX, Raman, and EDX to evaluate morphology, uniformity, crystallinity, and composition, and elemental distribution of compounds on the electrode. The overpotential parameters for hydrogen release reaction, stability, and charge transfer resistance will be studied by electrochemical techniques. The faradaic efficiency for the reaction will be evaluated by gas chromatography in operand with stability tests. It is expected with this to evaluate the viability of using 3D printing to obtain electrodes for the production of hydrogen and compare the two methodologies for electrode modification. (AU)