Carbon as a multifunctional material in supporting adsorption performance for water treatment: Science mapping and review

This review article aims to present the evaluation of research progress in the field of adsorption, identified based on 35,245 articles from 2003–2023 utilizing the Scopus database via bibliometric analysis to determine the countries, most active journals, and keyword relationships that indicate knowledge-exchange and collaboration pathways. The role of density functional theory and the second-order (Y) of adsorption modelling such as response surface methodology and artificial neural networks from input items (adsorbent concentration x_i, adsorbent type x_i2, etc.) has become an option for designing the optimization of specific pollutant degradation as output due to its controllability in optimized experimental conditions for maximum adsorption efficiency. Meanwhile, the development of isotherm models from Freundlich in 1906 to Liu in 2018 shows that adsorption intensity affects the k_f by changing the thermodynamic conditions as a consequence. To summarize, the optimization of adsorption properties through various methods and models has led to significant research on carbon and activated carbon (AC) for water remediation, with a trend towards using AC with semiconductors and exploring multifunctional applications. Additionally, carbon (black, fiber, nanotube form) and AC are discussed as materials that have been employed in the fields of civil engineering, energy storage, biomedicine, and sensors due to their conductivity, specific surface area, and detoxification properties. Finally, this review is beneficial for researchers focused on finding the scientific justification and development of carbon and AC as promising adsorbents.