Analyzing the trends and hotspots of biochar’s applications in agriculture, environment, and energy: a bibliometrics study for 2022 and 2023

Abstract

Biochar, produced from the thermochemical conversion of biomass waste, has various applications owing to its broad utility and advantageous properties. This study employs a scientometric approach to comprehensively assess the advancements in biochar application from 2022 to 2023. Utilizing 13,357 bibliographic records sourced from the Web of Science Core Collection with the search term “biochar”, the analysis focuses on authorship, national contributions, and keyword trends. Findings demonstrate a continual rise in annual publications since 2009, albeit with a moderated growth rate in 2023. China leads in publication outputs, followed by USA and India, with Hailong Wang emerging as a prominent figure in biochar research. Keyword co-occurrence analyses identify key research themes such as biochar’s role in climate change mitigation, easing salinity and drought stress, immobilizing toxic metals, degrading organic pollutants, serving as additives in anaerobic digestion, and functioning as electrodes in microbial fuel cells. Among these, biochar’s application for global climate change mitigation gains significant attention, while its utilization as electrodes in microbial fuel cells emerges as a promising research frontier, indicating the growing need for sustainable energy sources. The study also outlines critical research gaps and future priorities for enhancing biochar application. Overall, it highlights the diverse applicability of biochar and offers valuable insight into research progression and forthcoming directions in biochar studies.

Highlights

•	Utilization of bibliometric review for keyword analysis.
•	Examination of recent developments in biochar application.
•	The emerging focus on biochar’s effectiveness as electrodes in microbial fuel cells (MFCs).
•	Suggested future research directions and priorities for sustainable biochar application.

Keywords

Bibliometric analysis / Research hotspots / Carbon neutrality / Microbial fuel cells / Sustainable application

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Funding

central guided local science and technology development funds of hebei province(236Z7303G); Strategic Priority Research Program of the Chinese Academy of Science(XDA0440103); Natural Science Foundation of Hebei Province(C2023503008); China National Tobacco Corporation Guizhou Provincial Company Science and Technology Program(2022XM11); Guangdong Foundation for Program of Science and Technology Research, China(2023B1212060044); National Science Fund for Distinguished Young Scholars(42225701)