Research advances of rare earth catalysts for catalytic purification of vehicle exhausts - Commemorating the 100th anniversary of the birth of Academician Guangxian Xu

Nowadays, air pollution has become a prominent environmental problem and has attracted much attention. With the increase of vehicle retention quantity, the exhaust emissions have become the main sources of air pollution. To reduce pollution and hazards, vehicle exhaust emission regulations are becoming stricter and stricter, which puts forward higher requirements for purification of vehicle exhausts. At present, rare earths have been widely applied in vehicle exhaust purification because of their good catalytic performance, which is attributed to their unique 4f electron layer structure occupied without full electrons, excellent oxygen storage/release capacity and redox ability. In this paper, the current status of rare earth catalysts and application of rare earth in different fuel vehicle exhaust catalysts, including three-way catalysts (TWCs) for gasoline vehicles, diesel exhaust catalysts for different pollutants (particulate matter (PM), NOx, CO and HC) and catalysts for new energy vehicles with different fuels, are summarized in detail. Meanwhile, the corresponding mechanisms and the role of rare earth in vehicle exhaust catalysts are also simultaneously described. Furthermore, the challenges and development directions of rare earth catalysts for the purification of vehicle exhausts are also proposed. (C) 2021 Published by Elsevier B.V. on behalf of Chinese Society of Rare Earths.

Automated summary

The article summarizes the increasingly prominent issue of air pollution, with vehicle exhaust emissions becoming a major source of pollution, and rare earth catalysts becoming an important choice for vehicle exhaust purification due to their unique properties. It also describes the current status, application, and role of rare earth catalysts in different vehicle exhausts, and proposes future directions for development.