Titanium anode (MMO) is made of precious metal iridium salt coated on titanium substrate and sintered at high temperature. It is widely used in electroplating (high-requirement copper electroplating and gold electroplating in the circuit board industry), electrolysis and other hydrometallurgical activities. The preparation and application of the electrode are quite mature. Compared with the traditional platinized electrode in the alkaline copper plating process, the titanium anode has the incomparable advantages of the platinized electrode:
1, technical characteristics
High current efficiency, excellent antibacterial corrosion performance; long electrode life; can withstand higher current density, operating current density; <10000A/M2 belongs to the oxygen evolution anode based on industrial pure titanium
2, high catalytic activity
As we all know, the platinum-plated electrode is a high over-oxygen potential (1.563V, relative to mercury sulfate) electrode, while the MMO anode is a low oxygen evolution over-potential (1.385V relative to mercury sulfate) electrode, which is more effective in the anode oxygen evolution zone. Easily release oxygen. Therefore, during electrolysis, the cell pressure is relatively low, which saves electricity. This phenomenon is obviously manifested in the alkaline copper plating wall after the alkaline treatment of the copper foil.
3, pollution-free MMO
The anode coating is a ceramic oxide of the noble metal iridium, which is a fairly stable oxide, almost insoluble in any acid and alkali, and the oxide coating is about 20-40um, and the overall coating oxide is less . Therefore, the MMO anode will not pollute the electroplating solution, which is basically the same as the platinum-plated electrode.
4, high cost performance
The same service life of platinum-plated electrodes (with a coating thickness of 3.5 microns) has been maintained. The price of MMO anodes is about 80% of that of platinum-plated electrodes. MMO electrodes have better electrochemical stability in alkaline copper electroplating electrolytes. It has excellent electrolytic activity and durability. From the analysis of the cost of the company’s MMO anode and PT electrode, it is obvious that the MMO electrode is economical.
- Since the application of copper in printed circuit boards requires the use of pulse cycle reversal (PPR) technology, we know that the use of platinum-plated insoluble anodes is prohibited (the oxide in the sulfuric acid electrolyte exists in this current loop, and after a period of time Will peel off the platinum layer). However, the use of dimensionally stable anodes can avoid this phenomenon and enable the insoluble anode technology to successfully achieve performance advantages in this application.
6. Anode maintenance is minimal. There is no need to stop the production line to clean and replenish anodes, replace anode bags and re-plating anodes (increased productivity and reduced labor costs);
7. The life of the insoluble anode depends on the type, working current density and contact with various electroplating chemicals.