A recent bibliometric analysis in the journal ACS ES&T Water by Darliane Cristina Soares de Souza, Juciane Vieira de Assis Freire, and colleagues illuminates the global research landscape for using biochar in carbon sequestration and modeling. The findings reveal a field undergoing rapid expansion and intellectual concentration. Between 2009 and 2025, scientific publications on biochar, carbon sequestration, and modeling totaled 448 articles, sourced from the Web of Science database.

The most compelling finding is the remarkable acceleration of research output. In the period from 2012 to 2019, publications maintained a modest pace, averaging around 20 articles annually. However, the landscape fundamentally changed around 2020. From 2020 to 2024, the average number of yearly publications soared to 58, with nearly 80 articles published in 2024 alone. This exponential growth signifies a global recognition of biochar as a critical climate mitigation and carbon dioxide removal (CDR) strategy.

Geographically, the field is dominated by a few key players. China is the unquestioned leader in volume, contributing 153 articles, followed by the United States with 91, and Australia with 35. China’s institutional commitment is also evident, with the Chinese Academy of Sciences ranking first with 30 publications. While China leads in publication volume, other countries show a higher average citation rate (AC factor), which suggests a more concentrated impact per paper. For instance, the journal Chemosphere holds the highest total number of citations at 3,404, while Yong Sik Ok is the most cited researcher, boasting 4,248 citations.

Research priorities are clearly evolving. The most prominent keywords beyond “biochar” itself include “carbon sequestration” (104 mentions), “sequestration” (79), and “pyrolysis” (72). However, a temporal analysis of keywords demonstrates a distinct shift. Initial research (2017-2018) focused heavily on water-related themes such as “aqueous solution,” “activated carbonActivated carbon is a form of carbon that has been processed to create a vast network of tiny pores, increasing its surface area significantly. This extensive surface area makes activated carbon exceptionally effective at trapping and holding impurities, like a molecular sponge. It is commonly More,” and “sorption” for pollutant removal. More recent studies, from 2020 to 2022, have increasingly concentrated on soil health, including “microbial community,” “mineralization,” “decomposition,” and “life-cycle assessment”. This signals a growing maturity in the field, moving past basic applications toward complex, long-term modeling of biochar’s fate in diverse ecosystems to accurately quantify its persistent carbon storage potential.

The intellectual structure of the field is highly interdisciplinary, with the top research areas being Environmental Sciences (37%), Soil Science (11%), Environmental Engineering (11%), and Energy and Fuels (11%). This diversity reflects biochar’s multifunctional nature, offering benefits that span from improving soil fertility and water retention (agronomic benefits) to sequestering carbon and reducing greenhouse gas emissions (environmental benefits).

Source: Souza, D. C. S. de, Freire, J. V. de A., da Silva, L. F., da Silva, P. P., Antunes, L. F. de S., Souto, A. G. de L., Valença, R. D., Fernandes, B. C. C., de Oliveira Lima, A. E., dos Santos, J. C. S., Silva, D. V., do Carmo, F. R., & Melo, R. L. F. (2025). Carbon Sequestration with Biochar: Global Trends, Knowledge Gaps, and Future Directions. ACS ES&T Water.