Bibliometric Analysis and Thematic Evolution of Advanced Oxidation Processes for Persistent Organic Pollutant Degradation (2000–2026)

Pollution by persistent organic pollutants (POPs) constitutes an environmental and public health crisis of planetary scale due to their toxicity, persistence, and capacity for bioaccumulation in ecosystems. Given the limitations of conventional methods, which are often costly or generate hazardous byproducts, advanced oxidation processes (AOPs) have emerged as critical alternatives for the terminal destruction of these compounds. However, a persistent gap remains between laboratory-scale innovations and their real industrial application. To address this issue, the study employs a systematic and quantitative bibliometric analysis of the scientific literature produced between 2000 and 2026. A total of 5911 documents indexed in Scopus were analyzed using specialized tools such as R Studio (bibliometrix) 2026.04.0+526 and VOSviewer (1.6.20) to map productivity, impact, and the intellectual structure of the field through co-occurrence networks and international collaboration. The results demonstrate exponential growth in research, with an annual rate exceeding 18%. China leads scientific production with 109 publications, while Spain and France record the highest impact per article, with averages of 217.5 and 213.5 citations respectively, underscoring the influence of their researchers as theoretical and methodological benchmarks. Authors such as Malato (Spain) and Oturan (France) act as central nodes of international collaboration, accumulating thousands of citations in areas such as solar photocatalysis and electro-Fenton processes. The analysis confirms that solar photocatalysis and electrochemical processes are the most effective AOP families, consistently reporting degradation efficiencies above 85–90%. Wastewater treatment is identified as the primary research driver, while advanced catalyst design has evolved into a niche technical specialization. Journals such as Chemosphere and Science of the Total Environment have consolidated as the main dissemination channels for this research.