Bibliometric Based Analysis of Hydrogels in the Field of Water Treatment

Hydrogels exhibit distinctive features. These properties make them suitable for applications across various fields, such as environment, energy, and medicine. In this paper, we conducted a comprehensive search on the CNKI and Web of Science databases spanning from 2000 to 2024. Using tools like CiteSpace and VosViewer, we visualized the evolution, composition, hot spots, and trends in hydrogels in the field of water treatment sustainability. The results show that from 2000 to 2024, there has been a gradual increase in the number of publications in this field. China leads in the total number of publications; although, it ranks fourth in average citation rate. Seven out of the top ten research institutions are based in China. Additionally, three journals, including the International Journal of Biological Macromolecules, Chemical Engineering Journal and Carbohydrate Polymers, stand out, with a relatively high number of publications. The identified research hotspots include a range of preparation methods, including the freezing method and cross-linking method. Additionally, other preparation methods and the examination of water retention rate and adsorption isotherm are part of the research focus. The primary emphasis is on studying the adsorption of heavy metals, microplastics, and organic pollutants in dye wastewater. The main adsorption mechanisms investigated are chelation, electrostatic attraction, and functional group interaction. These findings have potential applications in water purification, seawater desalination, and atmospheric condensation. For the authorized patents in hydrogel-related fields, with the continuous improvement in innovation ability and the continuous enhancement of intellectual property protection awareness, the number of authorized patents continues to rise. China has seven of the top ten institutions in the number of patents granted, and the total number of patents granted in China ranks first in the world. Future work should focus on methods for synthesizing new pollutants and other target pollutants and on improving adsorption efficiency. Additionally, the development of cost-effective hydrogel materials with improved treatment efficacy is essential to advance sustainable practices in water treatment.