Technological breakthrough! The best alternative to hydrogen fuel cell catalysts is born, reducing costs by 80%

Platinum costs about RMB 193 per gram. In addition to appearing in jewelry windows in department stores, people can also find it in the list of raw materials for hydrogen fuel cell catalysts. This is the reason why the price of hydrogen fuel cells is rising instead of falling.

However, Princeton University recently successfully found a potential alternative that costs only one-fifth of platinum catalysts, which may have the opportunity to reduce battery costs in the future.

Hydrogen fuel cells use the chemical changes of hydrogen and oxygen to generate electricity. Hydrogen enters from the anode of the fuel cell and is decomposed into hydrogen ions and electrons through the anode catalyst. The electrons then form an electric current through an external circuit and reach the cathode. After the hydrogen loses its electrons, it passes through the electrolyte to the cathode next door; the cathode is where oxygen enters, and the hydrogen ions, electrons and oxygen react with the help of the cathode catalyst to produce water.

It does not emit any exhaust gas, only produces water and heat. The above characteristics make hydrogen fuel cells regarded as one of the alternative energy sources for fossil fuels, and are also a highly anticipated source of electricity for electric vehicles. Unfortunately, platinum, used as a catalyst, is very expensive and its content in the earth's crust is not high. Therefore, hydrogen fuel cells cannot be adopted on a large scale by all walks of life. Although scientists have also thought about using other metals, alloys or compounds to make catalysts, their performance is not as good as platinum.

Scientists have repeatedly encountered setbacks in past experiments. Although the performance of alloy catalysts can surpass that of platinum at the beginning, they will begin to oxidize and leach after a while. If cheaper metals are used as catalysts, the catalyst dosage must be increased, which will cause too much catalyst to adhere to the electrode, thereby reducing energy efficiency.

In this regard, Bruce E. Koel, professor of biological and chemical engineering at Princeton University, said that platinum catalysts are almost perfect, with fast electrochemical reactions and the ability to withstand harsh acidic conditions, but in fact alternatives do not need to be as perfect as platinum.

The team's research found that low-conductivity materials that have never been noticed in the past can also be transformed after special treatment. For example, hafnium oxide treated with nitrogen plasma can not only be transformed into a thin film material, but also become a highly active catalyst that can withstand strong acids. It may be a good substitute for platinum catalysts.

Research tests show that although the efficiency of the new hafnium thin film catalyst is only 60% of that of platinum, it has the advantage of low cost, which is one-fifth of platinum. In addition to being used in hydrogen fuel cells, it can also be used in the field of electrochemical water decomposition to produce hydrogen. Xiaofang Yang, a scientist from the cooperative enterprise HiT Nano, pointed out that electrolysis of water to produce hydrogen is also an important part of the renewable energy economy, and the importance of this research is self-evident.

The team will also consider testing cheaper zirconium in the future, but it is still unclear whether this research can further reduce the cost of hydrogen fuel. Scientists cannot bring new catalysts and research out of the laboratory, and they also have to consider the cost of large-scale production. It can only be said that scientists have opened up another possibility through this research. Koel pointed out that the team is not clear about the reason for the research yet, and they have to continue to study the special properties of the material.

The current research has been published in Nature Communications.