Use of Nanoparticles in Vapor Compression Refrigeration Systems: A Bibliometric Approach

Objective: The objective of this study is to map the scientific production on the use of nanoparticles in vapor compression refrigeration systems, with emphasis on the doping of lubricating oils, aiming to identify trends, gaps, and research opportunities. Theoretical Framework: The literature indicates that the incorporation of nanoparticles into thermal fluids and lubricants can enhance thermal conductivity, improve heat dissipation, and reduce friction and wear in compressors. However, integrative quantitative reviews remain scarce, particularly regarding tribological performance. Method: A systematic bibliometric review was conducted using data from the Scopus and Web of Science databases, processed in the RStudio environment with the Bibliometrix and Biblioshiny packages. Filters were applied to eliminate duplicates and standardize metadata, enabling analyses of temporal evolution, keywords, co-authorship networks, and the most productive institutions. Results and Discussion: A total of 182 publications were identified between 2012 and 2025, with an average annual growth rate of 8.82%. A predominance of studies focused on thermal properties was observed, while tribological aspects appeared with low frequency. India stood out as the leading contributor, and low international collaboration (6.04%) was recorded. Research Implications: The findings highlight the need to deepen investigations into tribological performance and practical applications of nanolubricants in vapor compression cycles, as well as to expand international collaborations for the consolidation of the field. Originality/Value: This study contributes by quantitatively and systematically consolidating the global research landscape on the doping of lubricating oils with nanoparticles, providing insights to advance sustainable refrigeration solutions.