In the development of fuel cells, optimizing catalyst performance has always been a key research focus. In recent years, an innovative technology—ultrasonic dispersion—has gradually emerged, bringing significant breakthroughs in improving the activity of fuel cell catalysts.
Ultrasonic dispersion technology mainly utilizes cavitation microjets and high-frequency shear forces. In practical applications, when ultrasound is applied to a solution containing Pt/C agglomerates, the ultrasound propagates in the liquid, generating alternating high-pressure and low-pressure cycles. During the low-pressure cycle, tiny vacuum bubbles, i.e., cavitation bubbles, are formed. These bubbles grow continuously through multiple pressure cycles until they reach a size where they can no longer absorb energy. At this point, the cavitation bubbles violently implode, creating extremely extreme local conditions. Under these extreme conditions, cavitation microjets and high-frequency shear forces can effectively deagglomerate Pt/C agglomerates while simultaneously stripping surface impurities. Related research data shows that this treatment can improve the activity of fuel cell catalysts by more than 30%. This significant improvement promises a qualitative leap in key performance indicators such as energy conversion efficiency for fuel cells.
However, a key challenge in applying ultrasonic dispersion technology is avoiding damage to the support. Research has found that strictly controlling the "power-time-temperature" triangle is crucial to solving this problem. Excessive power, prolonged time, or improper temperature control can all potentially cause irreversible damage to the support structure, thus affecting the overall performance of the catalyst. To effectively address this challenge, researchers innovatively combined pulse cooling with a dispersion stabilizer. Pulse cooling effectively removes the heat generated during ultrasonic waves, preventing damage to the support due to excessive temperature. The addition of a dispersion stabilizer forms a protective film on the catalyst particle surface, further stabilizing the catalyst structure and reducing particle agglomeration caused by ultrasonic waves. Through the synergistic effect of these two technologies, a high-performance catalyst slurry capable of meeting the requirements of automotive fuel cells (>1W/cm²) has been successfully prepared.
From a broader perspective, ultrasonic dispersion technology has opened up a completely new path for the preparation of fuel cell catalysts. It not only significantly improves catalyst activity but also effectively solves key problems such as support damage, laying a solid foundation for improving the performance of automotive fuel cells. With ongoing research and technological optimization, ultrasonic dispersion technology is expected to play a more significant role in the fuel cell field, driving greater breakthroughs in fuel cell technology and providing strong support for the widespread application of clean energy in the future.
