BIBLIOMETRIC ANALYSIS OF NITROGEN DIOXIDE EXPOSURE RESEARCH USING VOSVIEWER

Abstract

Background: Nitrogen dioxide (NO₂) is one of the most critical air pollutants, contributing to both environmental degradation and human health risks. In recent years, research on nitrogen dioxide and its environmental impacts has grown significantly, reflecting global concern over pollution control and sustainable energy development. Object: his study aims to examine the trends, patterns, and thematic evolution of international research on nitrogen dioxide through bibliometric analysis, identifying key topics, publication dynamics, and emerging research directions. Methods: A bibliometric approach was employed using data retrieved from the Scopus databases, covering the years 2010–2025. The analysis included document types, subject areas, and keyword co-occurrence mapping generated with VOSviewer software to visualize relationships, trends, and research intensity across thematic cluster. Results: A total of 434 publications were identified, showing a significant upward trend from 2010 to 2025, peaking in 2017 with 34 publications (7.83%). Most were research articles (372), followed by conference papers (27) and review articles (26). The leading subject areas were Environmental Science (211 publications) and Chemistry (122). Keyword analysis revealed 15 thematic clusters, demonstrating strong relationships among nitrate, nitrite, and nitrogen dioxide, with emerging themes such as nitrate reduction and electrocatalysis in recent years. Conclusion: Research on nitrogen dioxide has transitioned from conventional environmental and chemical studies toward innovative topics in electrocatalytic processes and sustainable energy.