Nano-biochar research: A scopus-based bibliometric analysis of the 2016–2025 period

Nano-biochar has emerged as a promising material for environmental remediation, sustainable agriculture, and advanced material applications. Despite its growing importance, an understanding of research trends, leading contributors, and thematic evolution remains limited. This study performs a bibliometric analysis of nano-biochar research using the Scopus database, covering the period 2016–2025 and encompassing 261 peer-reviewed documents published in English. The analysis is based on data from a single database and is therefore representative of Scopus-indexed literature. The analysis shows rapid publication growth, from a single publication in 2016–75 in 2025, accompanied by an increase in annual citations, reaching 2746 in 2025, showing the field's expanding influence and cross-disciplinary relevance. Research output is concentrated in key journals such as Science of the Total Environment, Journal of Cleaner Production, and Environmental Science: Nano, with the National Natural Science Foundation of China being the most prolific funding agency. Keyword co-occurrence and clustering analysis identify six thematic clusters: adsorption-based water treatment, biological interactions and environmental fate, sustainable agriculture, material synthesis and properties, heavy metal remediation, and surface charge characterization. Environmental science is the dominant subject area, followed by chemical engineering, chemistry, and agricultural and biological sciences. The findings indicate a maturation of the field, marked by a shift from foundational material characterization toward performance-driven applications, predictive modelling, and sustainability-focused research. This study provides a structured foundation for guiding future research efforts toward standardization, scalable synthesis, and responsible large-scale implementation of nano-biochar technologies.