fuel cell electrode materials

fuel cell electrode materials information as follows:A fuel cell is a power generation device that directly converts the chemical energy present in fuel and oxidant into electrical energy. Fuel and air are fed into the fuel cell separately, and electricity is produced wonderfully. From the appearance, it has positive and negative electrodes and electrolyte, etc., like a storage battery, but in essence it can not “storage” but a “power plant”.

The electrode of the fuel cell is the electrochemical reaction site where the fuel undergoes an oxidation reaction and the oxidant undergoes a reduction reaction. The key to its performance lies in the performance of the catalyst, the electrode material, and the electrode manufacturing process.

Commonly used fuel cell electrodes are:

①Hydroxy fuel cell:

Hydrogen-oxygen fuel cells are generally made of inert metal platinum (Pt), titanium material coating or graphite as the electrode material, the negative electrode leads to H2, the positive electrode leads to O2,

The total reaction is: 2H2+O2===2H2O

②Methanol fuel cell:

Methanol fuel cells use platinum as the pole and use alkali or acid as the electrolyte:

1. Alkaline electrolyte (KOH solution as an example)

Total reaction formula: 2CH4O+3O2+4KOH===2K2CO3+6H2O

2. Acidic electrolyte (H2SO4 solution as an example)

Total reaction: 2CH4O+3O2===2CO2+4H2O

③Methane fuel cell:

The methane fuel cell uses porous nickel plates as the poles, the electrolyte solution is KOH, and the generated CO2 also reacts with KOH to generate K2CO3, so the total reaction is: CH4

+2KOH+2O2===K2CO3+

3H2O.

④Aluminum-air-sea water battery:

my country’s first new seawater sign lamp using aluminum-air-seawater battery as an energy source, using seawater as an electrolyte, relies on oxygen in the air to continually oxidize aluminum to generate current. As long as the lamp is placed in the sea for a few minutes, it will emit a dazzling white light. The anode material of the power source is aluminum; the anode material of the power source is graphite, platinum mesh and other conductive inert materials.

The total reaction formula is: 4Al+3O2+6H2O===4Al(OH)3

The fuel cell electrode requires that it cannot be consumed in the reaction and must be quite active, that is, it must have a catalytic effect, reduce the conditions under which the reaction occurs, increase the speed of the reaction, and allow the reaction to proceed smoothly. Of course, the graphite electrode is the cheapest However, it may be a reaction that makes graphite difficult to carry out, but it can be smoothly carried out with other electrodes (such as platinum), which is one of the reasons that many theoretically feasible fuel cells are actually not easy to implement.

A fuel cell is a chemical device that directly converts the chemical energy possessed by fuel into electrical energy, also known as an electrochemical generator. It is the fourth power generation technology after hydropower, thermal power generation and atomic power generation. Because the fuel cell converts Gibbs free energy in the chemical energy of the fuel into electrical energy through an electrochemical reaction, it is not limited by the Carnot cycle effect, so the efficiency is high; in addition, the fuel cell uses fuel and oxygen as both The transmission components, so there is no noise raw material, and the harmful gas emitted is very little; sound pollution. This shows that from the perspective of saving energy and protecting the ecological environment, fuel cells are the most promising power generation technology.

Power generation device that directly converts chemical energy of fuel and oxidant into electrical energy through electrochemical reaction. The fuel cell can theoretically operate at a thermal efficiency close to 100%, which is very economical. At present, due to various technical factors, the various fuel cells in actual operation consider the energy consumption of the entire device system. The total conversion efficiency is mostly in the range of 45% to 60%. For example, the utilization of heat exhaust can reach more than 80%. In addition, the fuel cell device contains no or few moving parts, works reliably, requires less maintenance, and is quieter than traditional generator sets. In addition, the electrochemical reaction is clean and complete, and rarely produces harmful substances. All of this makes the fuel cell regarded as a promising energy power plant.

The fuel cell is an electrochemical power generation device, which converts chemical energy directly into electrical energy in an isothermal electrochemical manner without going through the heat engine process, and is not limited by the Carnot cycle, so the energy conversion efficiency is high, and there is no noise and no pollution , Is becoming the ideal way of energy utilization. At the same time, with the continuous maturity of fuel cell technology and the provision of sufficient natural gas sources for the West-East Gas Pipeline Project, there are broad prospects for the commercial application of fuel cells.

The fuel cell is an energy conversion device. It is based on the electrochemical principle, that is, the working principle of the original battery, which converts the chemical energy stored in the fuel and oxidant directly into electrical energy at an isothermal temperature. Therefore, the actual process is a redox reaction. The fuel cell is mainly composed of four parts, namely anode, cathode, electrolyte and external circuit. Fuel gas and oxidizing gas are introduced from the anode and cathode of the fuel cell, respectively. The fuel gas emits electrons on the anode, and the electrons are conducted to the cathode through an external circuit and combine with the oxidizing gas to generate ions. Under the action of an electric field, ions migrate to the anode through the electrolyte, react with the fuel gas, form a loop, and generate current. At the same time, due to its own electrochemical reaction and the internal resistance of the battery, the fuel cell will also generate a certain amount of heat. In addition to conducting electrons, the cathode and anode of the battery also act as a catalyst for the redox reaction. When the fuel is hydrocarbon, the anode requires higher catalytic activity. The anode and cathode are usually porous structure to facilitate the introduction of reaction gas and the discharge of products. The electrolyte plays the role of transferring ions and separating fuel gas and oxidizing gas. In order to block the mixing of the two gases and cause a short circuit in the battery, the electrolyte is usually a dense structure.

The principle of a fuel cell is an electrochemical device, and its composition is the same as that of a general battery. The single cell is composed of positive and negative electrodes (negative electrode is fuel electrode and positive electrode is oxidant electrode) and electrolyte. The difference is that the active material of a general battery is stored inside the battery, therefore, the battery capacity is limited. The positive and negative electrodes of the fuel cell itself do not contain active materials, but only a catalytic conversion element. Therefore, fuel cells are literally energy conversion machines that convert chemical energy into electrical energy. When the battery is in operation, fuel and oxidant are supplied from outside to react. In principle, as long as the reactants are continuously input and the reaction products are continuously eliminated, the fuel cell can continuously generate electricity. Here, a hydrogen-oxygen fuel cell is used as an example to illustrate the fuel cell

Hydrogen-oxygen fuel cell reaction principle This reaction is the reverse process of electrolyzed water. The electrode should be: negative electrode: H2+2OH-→2H2O+2e-

Positive electrode: 1/2O2+H2O+2e-→2OH-

Battery reaction: H2+1/2O2==H2O

In addition, only the fuel cell body cannot work,

The fuel cell must have a set of corresponding auxiliary systems, including reactant supply system, heat exhaust system, drainage system, electrical performance control system and safety device.

A fuel cell is usually composed of an electrolyte plate forming an ion conductor, fuel electrodes (anode) and air electrodes (cathode) arranged on both sides, and gas flow paths on both sides. The role of the gas flow path is to make fuel gas and air (oxidant Gas) can pass through the flow path.

BAOJI HIGHSTAR TITANIUM METAL provides titanium fuel cells for hydrogen production, the substrate is titanium material or titanium porous material, and the surface is coated with precious metals. For any inquiry, please feel free to contact us.