Preparation Of Nickel-based Transition Metal Electrode And Its Hydrogen-evolution Performance Of Electrolytic Of Water

At present,with the large consumption of fossil energy and the aggravation of carbon emission,hydrogen,as an environmental-friendly and efficient renewable energy,has attracted wide attention.Among many hydrogen production methods,electrolysis of water is one of the most environment-friendly and efficient method and the purest hydrogen production are available.However,the most widely used Pt-based electrode materials are limited because of their high cost and low reserves.Therefore,the development and preparation of non-noble metal-based electrolytic water cathode material with excellent performance is one of the researching focuses of energy development in recent years.Ni,as a homologous group element of Pt,has been extensively studied in the field.Due to the inherent properties of Ni,it is necessary to optimize the electrocatalytic activity of Ni from two aspects: modifying the surface to increase the hydrogen-evolution active surface area;introducing other elements to promote elemental synergy.In this study,three Ni-based transition metal catalyst electrodes with special micromorphology were successfully prepared by using a novel gradient electrodeposition method and introducing S,Co and Mn element.The electrocatalytic performance of electrodes were tested,and surface structure and morphology,composition and elemental distribution of electrodes were characterized.Content is as follows:By the new gradient electrodeposition method and adjusting the concentration of electrolyte ions,the temperature and pH value of the electrolytic environment and other influencing factors,a novel amorphous Ni-S electrode with a large specific surface area and strong hydrogen-evolution properties with a multi-channel gully porous structure was prepared.The experiment result shows that the strong hydrogen evolution performance of Ni-S electrode is largely dependent on the more active hydrogen evolution sites caused by the super electrochemical surface area;Amorphous Ni can effectively enhance the adsorption of hydrogen atoms,and doped Ni3S2 greatly promotes the electron transfer rate and further improves the electrochemical performance;Due to the segmental deposition of gradient electrodeposition method,the electrode has a strong electrochemical stability while having a strong electrocatalytic performance.Based on the preparation of Ni-S electrode materials,Co element was introduced.By the new gradient electrodeposition method and adjusting the concentration of Co element in the electrolyte,a novel amorphous Ni-S-Co electrode with a very large specific surface area and super hydrogen-evolution properties with multi-channel coral forest porous structure was prepared.The experiment result shows that the size of deposited particles of Ni-S-Co electrode is greatly refined and has a larger active surface area,which further promotes the formation and desorption of hydrogen;Co element promotes the formation of Ni3S2 while forming Co4S3 itself,which improves the conductivity of the electrode.Based on the preparation of Ni-S electrode materials,Mn element was introduced.By the new gradient electrodeposition method and adjusting the concentration of Mn element in the electrolyte,a novel polycrystal Ni-S-Mn electrode with a very larger specific surface area and stronger hydrogen-evolution properties having a granular piled-up porous structure with spines on the surface was prepared.The experiment result shows that the structure of Ni-S-Mn electrode is composed of crystalline Ni3S2 and MnS slices as the skeleton and amorphous Ni as the filling;The newly added MnS flake compounds can promote electron transfer and further enhance the electrochemical stability and electrochemical surface area of the electrode.