Visualization and Analysis of Mapping Knowledge Domains for Coal Functional Groups

Abstract

ABSTRACT In this paper, a systematic review of the research on functional groups in coal is presented. In recent years, the research on functional groups in coal has been extended from the macroscopic level to the microscopic layer, and a large number of studies have shown that functional groups have significant effects on various properties of coal, such as gas adsorption and spontaneous combustion. To understand the current status and future trends of research on functional groups in coal, this study analyzed 3956 papers on this topic published in the Web of Science (WOS) core database from 2000 to 2022. The spatial and temporal distribution characteristics of publications, authors, countries, institutions, and major journals were visualized using VOSviewer and CiteSpace. Keyword co-occurrence and burst analysis are used to reveal the research status and hotspots in this field. The results show that the development of research on functional groups in coal goes through three stages: the fluctuating development period, the steady development period, and the results explosion period; China, USA, Australia, Japan, and India are the most active countries in the field of coal functional groups research, and China has a greater advantage in the number of publications and influence. A core group of institutions, mainly research universities, has been formed in this field, and Fuel, Energy and Fuels and Fuel Processing Technology are the main source journals for published results on coal functional groups. At present, the framework of basic theories and research methods is complete, and the study of functional groups for gas adsorption, the analysis of the evolution of functional groups in the process of coal thermodynamic behavior, and the characteristics of functional group categories and distribution in coal are the main knowledge framework basis for the study of functional groups in coal. The research on coal functional groups has been extended to the molecular level, and in the future, quantum chemistry, molecular simulation, and fine characterization research of functional groups will become the frontier of research in the field of coal functional groups.