Hydrogen energy is a clean energy source. With the increasing emergence of environmental protection issues in China, the use of natural renewable water resources to produce hydrogen is an important method in the future. For a long time, research on reducing the oxygen evolution overpotential of anodic hydrogen produced by electrolyzed water has focused on the selection of electrode materials and the modification of electrode surface. How to scientifically, effectively and reasonably select suitable electrode materials and cooperate with relevant technical means to further improve its activity is of great significance for greatly improving hydrogen production efficiency and reducing hydrogen production cost. Studying new oxygen-discharging electrodes, selecting suitable electrode materials, and improving the electrolysis efficiency in the electrolyzed water process. For the electro-hydraulic water-making hydrogen industry, both energy saving and efficiency improvement, as well as long-term solution to energy shortages, are very Important practical significance.
The current major hydrogen production processes include:
1. Hydrogen is produced from fossil fuels, and the hydrogen produced is mainly used as chemical raw materials, such as synthetic ammonia and synthetic methanol.
2. Biomass produces hydrogen through gasification and microbial production;
3, through a variety of chemical processes, such as electrolysis salt alkali industry, fermentation wine production process, synthetic ammonia fertilizer industry, petroleum refining industry, etc. have a large number of by-product hydrogen generation;
4. Electrolytic water to produce hydrogen is one of the methods that are widely used and widely applied.
Hydrogen production from electrolyzed water is an important means to achieve industrialized and inexpensive production of H2, and a product with a purity of 99.% to 99.9% can be obtained. Hydrogen production from electrolyzed water will be the core technology of the future hydrogen industry, with high social and economic benefits.
An important part of the water electrolysis hydrogen production equipment is the electrolysis cell, which is the key to the electrolysis cell. The quality of the electrode largely determines the tank voltage level and energy consumption of the water electrolysis, and directly affects the cost. The electrolyzed water reaction is carried out in an electrolytic cell filled with an electrolyte, and the electrolytic cell is divided into an anode chamber and a cathode chamber by a separator, and electrodes are respectively mounted in the two chambers. Since the conductivity of water is small, when an electric solution (about 15%) to which an electrolyte is added is passed through the electrode at a constant voltage, hydrogen gas is generated at the cathode, and oxygen is generated at the anode to thereby electrolyze the water. In theory, platinum metal is an ideal metal material for electrolyzed water, but because of the high cost, in order to reduce the production cost in practice, an alternative electrode material can be selected.
Evaluating the excellence of the electrode material, the service life and energy consumption of the electrode material are key factors. In practical applications, the following requirements should be met: good electrical conductivity, good electrocatalytic activity, chemical stability and mechanical stability. Can withstand large current density, long service life, reduce the requirements of hydrogen evolution, oxygen evolution overpotential.