Global research on the air quality status in response to the electrification of vehicles

Electric vehicles (EVs) can substantially decrease atmospheric pollutant emissions, thereby improving air quality, decreasing global warming, and improving human health. In this study, we performed a comprehensive bibliometric analysis using Web of Science to understand the research developments and future perspectives in EVs between 1974 and 2021. The analysis of indicators such as research trends, publication growth, and keywords revealed that most research in the selected timeframe was focused on applying and optimizing the existing technologies of different types of EVs to decrease air pollution and mortality. The changes in air quality owing to such electrification received special attention, with approximately 441 publications preferably in the English language. Among all the retrieved documents, research articles were most common (n = 295; 66.89% of the global output), dominated by the research domains of environmental sciences, followed by energy fuels and transportation science technology. Journal analysis revealed that Sustainability (n = 19, 4.30%) was the leading journal, followed by Journal of Cleaner Production and Science of the Total Environment. The most frequently used keywords were "electric vehicles," "air quality," and "air pollution." The most highly impactful article was published by Jacobson et al. (2005) in Science, with 620 total citations and 38.82 average annual citations. Furthermore, the United States (n = 118; 26.75% of the global output) had the highest publication rate, followed by China and the United Kingdom. The leading institutions were Tsinghua University (n = 16; 3.62% of the global research output) in China, followed by the University of Michigan and Cornell University in the United States. The current analysis warrants more focus on comprehensive analysis employing transport and chemistry modeling and using the latest technology for long life and sustainable batteries. This study provides a basis for future studies on improving air quality through innovative work in the electrification of vehicles.